Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1269 insertions, 0 deletions

diff --git a/layout/xul/tree/nsTreeContentView.cpp b/layout/xul/tree/nsTreeContentView.cpp
new file mode 100644
index 0000000000..edb5368e2a
--- /dev/null
+++ b/layout/xul/tree/nsTreeContentView.cpp
@@ -0,0 +1,1269 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsNameSpaceManager.h"
+#include "nsGkAtoms.h"
+#include "nsTreeUtils.h"
+#include "nsTreeContentView.h"
+#include "ChildIterator.h"
+#include "nsError.h"
+#include "nsXULSortService.h"
+#include "nsTreeBodyFrame.h"
+#include "nsTreeColumns.h"
+#include "mozilla/ErrorResult.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/TreeContentViewBinding.h"
+#include "mozilla/dom/XULTreeElement.h"
+#include "nsServiceManagerUtils.h"
+#include "mozilla/dom/Document.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+// A content model view implementation for the tree.
+
+#define ROW_FLAG_CONTAINER 0x01
+#define ROW_FLAG_OPEN 0x02
+#define ROW_FLAG_EMPTY 0x04
+#define ROW_FLAG_SEPARATOR 0x08
+
+class Row {
+ public:
+  Row(Element* aContent, int32_t aParentIndex)
+      : mContent(aContent),
+        mParentIndex(aParentIndex),
+        mSubtreeSize(0),
+        mFlags(0) {}
+
+  ~Row() = default;
+
+  void SetContainer(bool aContainer) {
+    aContainer ? mFlags |= ROW_FLAG_CONTAINER : mFlags &= ~ROW_FLAG_CONTAINER;
+  }
+  bool IsContainer() { return mFlags & ROW_FLAG_CONTAINER; }
+
+  void SetOpen(bool aOpen) {
+    aOpen ? mFlags |= ROW_FLAG_OPEN : mFlags &= ~ROW_FLAG_OPEN;
+  }
+  bool IsOpen() { return !!(mFlags & ROW_FLAG_OPEN); }
+
+  void SetEmpty(bool aEmpty) {
+    aEmpty ? mFlags |= ROW_FLAG_EMPTY : mFlags &= ~ROW_FLAG_EMPTY;
+  }
+  bool IsEmpty() { return !!(mFlags & ROW_FLAG_EMPTY); }
+
+  void SetSeparator(bool aSeparator) {
+    aSeparator ? mFlags |= ROW_FLAG_SEPARATOR : mFlags &= ~ROW_FLAG_SEPARATOR;
+  }
+  bool IsSeparator() { return !!(mFlags & ROW_FLAG_SEPARATOR); }
+
+  // Weak reference to a content item.
+  Element* mContent;
+
+  // The parent index of the item, set to -1 for the top level items.
+  int32_t mParentIndex;
+
+  // Subtree size for this item.
+  int32_t mSubtreeSize;
+
+ private:
+  // State flags
+  int8_t mFlags;
+};
+
+// We don't reference count the reference to the document
+// If the document goes away first, we'll be informed and we
+// can drop our reference.
+// If we go away first, we'll get rid of ourselves from the
+// document's observer list.
+
+nsTreeContentView::nsTreeContentView(void)
+    : mTree(nullptr), mSelection(nullptr), mDocument(nullptr) {}
+
+nsTreeContentView::~nsTreeContentView(void) {
+  // Remove ourselves from mDocument's observers.
+  if (mDocument) mDocument->RemoveObserver(this);
+}
+
+nsresult NS_NewTreeContentView(nsITreeView** aResult) {
+  *aResult = new nsTreeContentView;
+  if (!*aResult) return NS_ERROR_OUT_OF_MEMORY;
+  NS_ADDREF(*aResult);
+  return NS_OK;
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(nsTreeContentView, mTree, mSelection,
+                                      mBody)
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(nsTreeContentView)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(nsTreeContentView)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsTreeContentView)
+  NS_INTERFACE_MAP_ENTRY(nsITreeView)
+  NS_INTERFACE_MAP_ENTRY(nsIDocumentObserver)
+  NS_INTERFACE_MAP_ENTRY(nsIMutationObserver)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsITreeView)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+NS_INTERFACE_MAP_END
+
+JSObject* nsTreeContentView::WrapObject(JSContext* aCx,
+                                        JS::Handle<JSObject*> aGivenProto) {
+  return TreeContentView_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+nsISupports* nsTreeContentView::GetParentObject() { return mTree; }
+
+NS_IMETHODIMP
+nsTreeContentView::GetRowCount(int32_t* aRowCount) {
+  *aRowCount = mRows.Length();
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetSelection(nsITreeSelection** aSelection) {
+  NS_IF_ADDREF(*aSelection = GetSelection());
+
+  return NS_OK;
+}
+
+bool nsTreeContentView::CanTrustTreeSelection(nsISupports* aValue) {
+  // Untrusted content is only allowed to specify known-good views
+  if (nsContentUtils::LegacyIsCallerChromeOrNativeCode()) return true;
+  nsCOMPtr<nsINativeTreeSelection> nativeTreeSel = do_QueryInterface(aValue);
+  return nativeTreeSel && NS_SUCCEEDED(nativeTreeSel->EnsureNative());
+}
+
+NS_IMETHODIMP
+nsTreeContentView::SetSelection(nsITreeSelection* aSelection) {
+  ErrorResult rv;
+  SetSelection(aSelection, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::SetSelection(nsITreeSelection* aSelection,
+                                     ErrorResult& aError) {
+  if (aSelection && !CanTrustTreeSelection(aSelection)) {
+    aError.ThrowSecurityError("Not allowed to set tree selection");
+    return;
+  }
+
+  mSelection = aSelection;
+}
+
+void nsTreeContentView::GetRowProperties(int32_t aRow, nsAString& aProperties,
+                                         ErrorResult& aError) {
+  aProperties.Truncate();
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+  nsIContent* realRow;
+  if (row->IsSeparator())
+    realRow = row->mContent;
+  else
+    realRow = nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+
+  if (realRow && realRow->IsElement()) {
+    realRow->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::properties,
+                                  aProperties);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetRowProperties(int32_t aIndex, nsAString& aProps) {
+  ErrorResult rv;
+  GetRowProperties(aIndex, aProps, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::GetCellProperties(int32_t aRow, nsTreeColumn& aColumn,
+                                          nsAString& aProperties,
+                                          ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell) {
+      cell->GetAttr(kNameSpaceID_None, nsGkAtoms::properties, aProperties);
+    }
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetCellProperties(int32_t aRow, nsTreeColumn* aCol,
+                                     nsAString& aProps) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  GetCellProperties(aRow, *aCol, aProps, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::GetColumnProperties(nsTreeColumn& aColumn,
+                                            nsAString& aProperties) {
+  RefPtr<Element> element = aColumn.Element();
+
+  if (element) {
+    element->GetAttr(nsGkAtoms::properties, aProperties);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetColumnProperties(nsTreeColumn* aCol, nsAString& aProps) {
+  NS_ENSURE_ARG(aCol);
+
+  GetColumnProperties(*aCol, aProps);
+  return NS_OK;
+}
+
+bool nsTreeContentView::IsContainer(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  return mRows[aRow]->IsContainer();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsContainer(int32_t aIndex, bool* _retval) {
+  ErrorResult rv;
+  *_retval = IsContainer(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+bool nsTreeContentView::IsContainerOpen(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  return mRows[aRow]->IsOpen();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsContainerOpen(int32_t aIndex, bool* _retval) {
+  ErrorResult rv;
+  *_retval = IsContainerOpen(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+bool nsTreeContentView::IsContainerEmpty(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  return mRows[aRow]->IsEmpty();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsContainerEmpty(int32_t aIndex, bool* _retval) {
+  ErrorResult rv;
+  *_retval = IsContainerEmpty(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+bool nsTreeContentView::IsSeparator(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  return mRows[aRow]->IsSeparator();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsSeparator(int32_t aIndex, bool* _retval) {
+  ErrorResult rv;
+  *_retval = IsSeparator(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsSorted(bool* _retval) {
+  *_retval = IsSorted();
+
+  return NS_OK;
+}
+
+bool nsTreeContentView::CanDrop(int32_t aRow, int32_t aOrientation,
+                                ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+  }
+  return false;
+}
+
+bool nsTreeContentView::CanDrop(int32_t aRow, int32_t aOrientation,
+                                DataTransfer* aDataTransfer,
+                                ErrorResult& aError) {
+  return CanDrop(aRow, aOrientation, aError);
+}
+
+NS_IMETHODIMP
+nsTreeContentView::CanDrop(int32_t aIndex, int32_t aOrientation,
+                           DataTransfer* aDataTransfer, bool* _retval) {
+  ErrorResult rv;
+  *_retval = CanDrop(aIndex, aOrientation, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::Drop(int32_t aRow, int32_t aOrientation,
+                             ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+  }
+}
+
+void nsTreeContentView::Drop(int32_t aRow, int32_t aOrientation,
+                             DataTransfer* aDataTransfer, ErrorResult& aError) {
+  Drop(aRow, aOrientation, aError);
+}
+
+NS_IMETHODIMP
+nsTreeContentView::Drop(int32_t aRow, int32_t aOrientation,
+                        DataTransfer* aDataTransfer) {
+  ErrorResult rv;
+  Drop(aRow, aOrientation, rv);
+  return rv.StealNSResult();
+}
+
+int32_t nsTreeContentView::GetParentIndex(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return 0;
+  }
+
+  return mRows[aRow]->mParentIndex;
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetParentIndex(int32_t aRowIndex, int32_t* _retval) {
+  ErrorResult rv;
+  *_retval = GetParentIndex(aRowIndex, rv);
+  return rv.StealNSResult();
+}
+
+bool nsTreeContentView::HasNextSibling(int32_t aRow, int32_t aAfterIndex,
+                                       ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  // We have a next sibling if the row is not the last in the subtree.
+  int32_t parentIndex = mRows[aRow]->mParentIndex;
+  if (parentIndex < 0) {
+    return uint32_t(aRow) < mRows.Length() - 1;
+  }
+
+  // Compute the last index in this subtree.
+  int32_t lastIndex = parentIndex + (mRows[parentIndex])->mSubtreeSize;
+  Row* row = mRows[lastIndex].get();
+  while (row->mParentIndex != parentIndex) {
+    lastIndex = row->mParentIndex;
+    row = mRows[lastIndex].get();
+  }
+
+  return aRow < lastIndex;
+}
+
+NS_IMETHODIMP
+nsTreeContentView::HasNextSibling(int32_t aRowIndex, int32_t aAfterIndex,
+                                  bool* _retval) {
+  ErrorResult rv;
+  *_retval = HasNextSibling(aRowIndex, aAfterIndex, rv);
+  return rv.StealNSResult();
+}
+
+int32_t nsTreeContentView::GetLevel(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return 0;
+  }
+
+  int32_t level = 0;
+  Row* row = mRows[aRow].get();
+  while (row->mParentIndex >= 0) {
+    level++;
+    row = mRows[row->mParentIndex].get();
+  }
+  return level;
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetLevel(int32_t aIndex, int32_t* _retval) {
+  ErrorResult rv;
+  *_retval = GetLevel(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::GetImageSrc(int32_t aRow, nsTreeColumn& aColumn,
+                                    nsAString& aSrc, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell) cell->GetAttr(kNameSpaceID_None, nsGkAtoms::src, aSrc);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetImageSrc(int32_t aRow, nsTreeColumn* aCol,
+                               nsAString& _retval) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  GetImageSrc(aRow, *aCol, _retval, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::GetCellValue(int32_t aRow, nsTreeColumn& aColumn,
+                                     nsAString& aValue, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell) cell->GetAttr(kNameSpaceID_None, nsGkAtoms::value, aValue);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetCellValue(int32_t aRow, nsTreeColumn* aCol,
+                                nsAString& _retval) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  GetCellValue(aRow, *aCol, _retval, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::GetCellText(int32_t aRow, nsTreeColumn& aColumn,
+                                    nsAString& aText, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  // Check for a "label" attribute - this is valid on an <treeitem>
+  // with a single implied column.
+  if (row->mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::label, aText) &&
+      !aText.IsEmpty()) {
+    return;
+  }
+
+  if (row->mContent->IsXULElement(nsGkAtoms::treeitem)) {
+    nsIContent* realRow =
+        nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+    if (realRow) {
+      Element* cell = GetCell(realRow, aColumn);
+      if (cell) cell->GetAttr(kNameSpaceID_None, nsGkAtoms::label, aText);
+    }
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::GetCellText(int32_t aRow, nsTreeColumn* aCol,
+                               nsAString& _retval) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  GetCellText(aRow, *aCol, _retval, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::SetTree(XULTreeElement* aTree, ErrorResult& aError) {
+  aError = SetTree(aTree);
+}
+
+NS_IMETHODIMP
+nsTreeContentView::SetTree(XULTreeElement* aTree) {
+  ClearRows();
+
+  mTree = aTree;
+
+  if (aTree) {
+    // Add ourselves to document's observers.
+    Document* document = mTree->GetComposedDoc();
+    if (document) {
+      document->AddObserver(this);
+      mDocument = document;
+    }
+
+    RefPtr<dom::Element> bodyElement = mTree->GetTreeBody();
+    if (bodyElement) {
+      mBody = std::move(bodyElement);
+      int32_t index = 0;
+      Serialize(mBody, -1, &index, mRows);
+    }
+  }
+
+  return NS_OK;
+}
+
+void nsTreeContentView::ToggleOpenState(int32_t aRow, ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  // We don't serialize content right here, since content might be generated
+  // lazily.
+  Row* row = mRows[aRow].get();
+
+  if (row->IsOpen())
+    row->mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::open, u"false"_ns,
+                           true);
+  else
+    row->mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::open, u"true"_ns,
+                           true);
+}
+
+NS_IMETHODIMP
+nsTreeContentView::ToggleOpenState(int32_t aIndex) {
+  ErrorResult rv;
+  ToggleOpenState(aIndex, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::CycleHeader(nsTreeColumn& aColumn,
+                                    ErrorResult& aError) {
+  if (!mTree) return;
+
+  RefPtr<Element> column = aColumn.Element();
+  nsAutoString sort;
+  column->GetAttr(kNameSpaceID_None, nsGkAtoms::sort, sort);
+  if (!sort.IsEmpty()) {
+    nsAutoString sortdirection;
+    static Element::AttrValuesArray strings[] = {
+        nsGkAtoms::ascending, nsGkAtoms::descending, nullptr};
+    switch (column->FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::sortDirection,
+                                    strings, eCaseMatters)) {
+      case 0:
+        sortdirection.AssignLiteral("descending");
+        break;
+      case 1:
+        sortdirection.AssignLiteral("natural");
+        break;
+      default:
+        sortdirection.AssignLiteral("ascending");
+        break;
+    }
+
+    nsAutoString hints;
+    column->GetAttr(kNameSpaceID_None, nsGkAtoms::sorthints, hints);
+    sortdirection.Append(' ');
+    sortdirection += hints;
+
+    XULWidgetSort(mTree, sort, sortdirection);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::CycleHeader(nsTreeColumn* aCol) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  CycleHeader(*aCol, rv);
+  return rv.StealNSResult();
+}
+
+NS_IMETHODIMP
+nsTreeContentView::SelectionChangedXPCOM() { return NS_OK; }
+
+NS_IMETHODIMP
+nsTreeContentView::CycleCell(int32_t aRow, nsTreeColumn* aCol) { return NS_OK; }
+
+bool nsTreeContentView::IsEditable(int32_t aRow, nsTreeColumn& aColumn,
+                                   ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return false;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell && cell->AttrValueIs(kNameSpaceID_None, nsGkAtoms::editable,
+                                  nsGkAtoms::_false, eCaseMatters)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+NS_IMETHODIMP
+nsTreeContentView::IsEditable(int32_t aRow, nsTreeColumn* aCol, bool* _retval) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  *_retval = IsEditable(aRow, *aCol, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::SetCellValue(int32_t aRow, nsTreeColumn& aColumn,
+                                     const nsAString& aValue,
+                                     ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell) cell->SetAttr(kNameSpaceID_None, nsGkAtoms::value, aValue, true);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::SetCellValue(int32_t aRow, nsTreeColumn* aCol,
+                                const nsAString& aValue) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  SetCellValue(aRow, *aCol, aValue, rv);
+  return rv.StealNSResult();
+}
+
+void nsTreeContentView::SetCellText(int32_t aRow, nsTreeColumn& aColumn,
+                                    const nsAString& aValue,
+                                    ErrorResult& aError) {
+  if (!IsValidRowIndex(aRow)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+
+  Row* row = mRows[aRow].get();
+
+  nsIContent* realRow =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treerow);
+  if (realRow) {
+    Element* cell = GetCell(realRow, aColumn);
+    if (cell) cell->SetAttr(kNameSpaceID_None, nsGkAtoms::label, aValue, true);
+  }
+}
+
+NS_IMETHODIMP
+nsTreeContentView::SetCellText(int32_t aRow, nsTreeColumn* aCol,
+                               const nsAString& aValue) {
+  NS_ENSURE_ARG(aCol);
+
+  ErrorResult rv;
+  SetCellText(aRow, *aCol, aValue, rv);
+  return rv.StealNSResult();
+}
+
+Element* nsTreeContentView::GetItemAtIndex(int32_t aIndex,
+                                           ErrorResult& aError) {
+  if (!IsValidRowIndex(aIndex)) {
+    aError.Throw(NS_ERROR_INVALID_ARG);
+    return nullptr;
+  }
+
+  return mRows[aIndex]->mContent;
+}
+
+int32_t nsTreeContentView::GetIndexOfItem(Element* aItem) {
+  return FindContent(aItem);
+}
+
+void nsTreeContentView::AttributeChanged(dom::Element* aElement,
+                                         int32_t aNameSpaceID,
+                                         nsAtom* aAttribute, int32_t aModType,
+                                         const nsAttrValue* aOldValue) {
+  // Lots of codepaths under here that do all sorts of stuff, so be safe.
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+
+  // Make sure this notification concerns us.
+  // First check the tag to see if it's one that we care about.
+  if (aElement == mTree || aElement == mBody) {
+    mTree->ClearStyleAndImageCaches();
+    mTree->Invalidate();
+  }
+
+  // We don't consider non-XUL nodes.
+  nsIContent* parent = nullptr;
+  if (!aElement->IsXULElement() ||
+      ((parent = aElement->GetParent()) && !parent->IsXULElement())) {
+    return;
+  }
+  if (!aElement->IsAnyOfXULElements(nsGkAtoms::treecol, nsGkAtoms::treeitem,
+                                    nsGkAtoms::treeseparator,
+                                    nsGkAtoms::treerow, nsGkAtoms::treecell)) {
+    return;
+  }
+
+  // If we have a legal tag, go up to the tree/select and make sure
+  // that it's ours.
+
+  for (nsIContent* element = aElement; element != mBody;
+       element = element->GetParent()) {
+    if (!element) return;                                // this is not for us
+    if (element->IsXULElement(nsGkAtoms::tree)) return;  // this is not for us
+  }
+
+  // Handle changes of the hidden attribute.
+  if (aAttribute == nsGkAtoms::hidden &&
+      aElement->IsAnyOfXULElements(nsGkAtoms::treeitem,
+                                   nsGkAtoms::treeseparator)) {
+    bool hidden = aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::hidden,
+                                        nsGkAtoms::_true, eCaseMatters);
+
+    int32_t index = FindContent(aElement);
+    if (hidden && index >= 0) {
+      // Hide this row along with its children.
+      int32_t count = RemoveRow(index);
+      if (mTree) mTree->RowCountChanged(index, -count);
+    } else if (!hidden && index < 0) {
+      // Show this row along with its children.
+      nsCOMPtr<nsIContent> parent = aElement->GetParent();
+      if (parent) {
+        InsertRowFor(parent, aElement);
+      }
+    }
+
+    return;
+  }
+
+  if (aElement->IsXULElement(nsGkAtoms::treecol)) {
+    if (aAttribute == nsGkAtoms::properties) {
+      if (mTree) {
+        RefPtr<nsTreeColumns> cols = mTree->GetColumns();
+        if (cols) {
+          RefPtr<nsTreeColumn> col = cols->GetColumnFor(aElement);
+          mTree->InvalidateColumn(col);
+        }
+      }
+    }
+  } else if (aElement->IsXULElement(nsGkAtoms::treeitem)) {
+    int32_t index = FindContent(aElement);
+    if (index >= 0) {
+      Row* row = mRows[index].get();
+      if (aAttribute == nsGkAtoms::container) {
+        bool isContainer =
+            aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::container,
+                                  nsGkAtoms::_true, eCaseMatters);
+        row->SetContainer(isContainer);
+        if (mTree) mTree->InvalidateRow(index);
+      } else if (aAttribute == nsGkAtoms::open) {
+        bool isOpen = aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::open,
+                                            nsGkAtoms::_true, eCaseMatters);
+        bool wasOpen = row->IsOpen();
+        if (!isOpen && wasOpen)
+          CloseContainer(index);
+        else if (isOpen && !wasOpen)
+          OpenContainer(index);
+      } else if (aAttribute == nsGkAtoms::empty) {
+        bool isEmpty =
+            aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::empty,
+                                  nsGkAtoms::_true, eCaseMatters);
+        row->SetEmpty(isEmpty);
+        if (mTree) mTree->InvalidateRow(index);
+      }
+    }
+  } else if (aElement->IsXULElement(nsGkAtoms::treeseparator)) {
+    int32_t index = FindContent(aElement);
+    if (index >= 0) {
+      if (aAttribute == nsGkAtoms::properties && mTree) {
+        mTree->InvalidateRow(index);
+      }
+    }
+  } else if (aElement->IsXULElement(nsGkAtoms::treerow)) {
+    if (aAttribute == nsGkAtoms::properties) {
+      nsCOMPtr<nsIContent> parent = aElement->GetParent();
+      if (parent) {
+        int32_t index = FindContent(parent);
+        if (index >= 0 && mTree) {
+          mTree->InvalidateRow(index);
+        }
+      }
+    }
+  } else if (aElement->IsXULElement(nsGkAtoms::treecell)) {
+    if (aAttribute == nsGkAtoms::properties || aAttribute == nsGkAtoms::mode ||
+        aAttribute == nsGkAtoms::src || aAttribute == nsGkAtoms::value ||
+        aAttribute == nsGkAtoms::label) {
+      nsIContent* parent = aElement->GetParent();
+      if (parent) {
+        nsCOMPtr<nsIContent> grandParent = parent->GetParent();
+        if (grandParent && grandParent->IsXULElement()) {
+          int32_t index = FindContent(grandParent);
+          if (index >= 0 && mTree) {
+            // XXX Should we make an effort to invalidate only cell ?
+            mTree->InvalidateRow(index);
+          }
+        }
+      }
+    }
+  }
+}
+
+void nsTreeContentView::ContentAppended(nsIContent* aFirstNewContent) {
+  for (nsIContent* cur = aFirstNewContent; cur; cur = cur->GetNextSibling()) {
+    // Our contentinserted doesn't use the index
+    ContentInserted(cur);
+  }
+}
+
+void nsTreeContentView::ContentInserted(nsIContent* aChild) {
+  NS_ASSERTION(aChild, "null ptr");
+  nsIContent* container = aChild->GetParent();
+
+  // Make sure this notification concerns us.
+  // First check the tag to see if it's one that we care about.
+
+  // Don't allow non-XUL nodes.
+  if (!aChild->IsXULElement() || !container->IsXULElement()) return;
+
+  if (!aChild->IsAnyOfXULElements(nsGkAtoms::treeitem, nsGkAtoms::treeseparator,
+                                  nsGkAtoms::treechildren, nsGkAtoms::treerow,
+                                  nsGkAtoms::treecell)) {
+    return;
+  }
+
+  // If we have a legal tag, go up to the tree/select and make sure
+  // that it's ours.
+
+  for (nsIContent* element = container; element != mBody;
+       element = element->GetParent()) {
+    if (!element) return;                                // this is not for us
+    if (element->IsXULElement(nsGkAtoms::tree)) return;  // this is not for us
+  }
+
+  // Lots of codepaths under here that do all sorts of stuff, so be safe.
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+
+  if (aChild->IsXULElement(nsGkAtoms::treechildren)) {
+    int32_t index = FindContent(container);
+    if (index >= 0) {
+      Row* row = mRows[index].get();
+      row->SetEmpty(false);
+      if (mTree) mTree->InvalidateRow(index);
+      if (row->IsContainer() && row->IsOpen()) {
+        int32_t count = EnsureSubtree(index);
+        if (mTree) mTree->RowCountChanged(index + 1, count);
+      }
+    }
+  } else if (aChild->IsAnyOfXULElements(nsGkAtoms::treeitem,
+                                        nsGkAtoms::treeseparator)) {
+    InsertRowFor(container, aChild);
+  } else if (aChild->IsXULElement(nsGkAtoms::treerow)) {
+    int32_t index = FindContent(container);
+    if (index >= 0 && mTree) mTree->InvalidateRow(index);
+  } else if (aChild->IsXULElement(nsGkAtoms::treecell)) {
+    nsCOMPtr<nsIContent> parent = container->GetParent();
+    if (parent) {
+      int32_t index = FindContent(parent);
+      if (index >= 0 && mTree) mTree->InvalidateRow(index);
+    }
+  }
+}
+
+void nsTreeContentView::ContentRemoved(nsIContent* aChild,
+                                       nsIContent* aPreviousSibling) {
+  NS_ASSERTION(aChild, "null ptr");
+
+  nsIContent* container = aChild->GetParent();
+  // Make sure this notification concerns us.
+  // First check the tag to see if it's one that we care about.
+
+  // We don't consider non-XUL nodes.
+  if (!aChild->IsXULElement() || !container->IsXULElement()) return;
+
+  if (!aChild->IsAnyOfXULElements(nsGkAtoms::treeitem, nsGkAtoms::treeseparator,
+                                  nsGkAtoms::treechildren, nsGkAtoms::treerow,
+                                  nsGkAtoms::treecell)) {
+    return;
+  }
+
+  // If we have a legal tag, go up to the tree/select and make sure
+  // that it's ours.
+
+  for (nsIContent* element = container; element != mBody;
+       element = element->GetParent()) {
+    if (!element) return;                                // this is not for us
+    if (element->IsXULElement(nsGkAtoms::tree)) return;  // this is not for us
+  }
+
+  // Lots of codepaths under here that do all sorts of stuff, so be safe.
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+
+  if (aChild->IsXULElement(nsGkAtoms::treechildren)) {
+    int32_t index = FindContent(container);
+    if (index >= 0) {
+      Row* row = mRows[index].get();
+      row->SetEmpty(true);
+      int32_t count = RemoveSubtree(index);
+      // Invalidate also the row to update twisty.
+      if (mTree) {
+        mTree->InvalidateRow(index);
+        mTree->RowCountChanged(index + 1, -count);
+      }
+    }
+  } else if (aChild->IsAnyOfXULElements(nsGkAtoms::treeitem,
+                                        nsGkAtoms::treeseparator)) {
+    int32_t index = FindContent(aChild);
+    if (index >= 0) {
+      int32_t count = RemoveRow(index);
+      if (mTree) mTree->RowCountChanged(index, -count);
+    }
+  } else if (aChild->IsXULElement(nsGkAtoms::treerow)) {
+    int32_t index = FindContent(container);
+    if (index >= 0 && mTree) mTree->InvalidateRow(index);
+  } else if (aChild->IsXULElement(nsGkAtoms::treecell)) {
+    nsCOMPtr<nsIContent> parent = container->GetParent();
+    if (parent) {
+      int32_t index = FindContent(parent);
+      if (index >= 0 && mTree) mTree->InvalidateRow(index);
+    }
+  }
+}
+
+void nsTreeContentView::NodeWillBeDestroyed(nsINode* aNode) {
+  // XXXbz do we need this strong ref?  Do we drop refs to self in ClearRows?
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+  ClearRows();
+}
+
+// Recursively serialize content, starting with aContent.
+void nsTreeContentView::Serialize(nsIContent* aContent, int32_t aParentIndex,
+                                  int32_t* aIndex,
+                                  nsTArray<UniquePtr<Row>>& aRows) {
+  // Don't allow non-XUL nodes.
+  if (!aContent->IsXULElement()) return;
+
+  dom::FlattenedChildIterator iter(aContent);
+  for (nsIContent* content = iter.GetNextChild(); content;
+       content = iter.GetNextChild()) {
+    int32_t count = aRows.Length();
+
+    if (content->IsXULElement(nsGkAtoms::treeitem)) {
+      SerializeItem(content->AsElement(), aParentIndex, aIndex, aRows);
+    } else if (content->IsXULElement(nsGkAtoms::treeseparator)) {
+      SerializeSeparator(content->AsElement(), aParentIndex, aIndex, aRows);
+    }
+
+    *aIndex += aRows.Length() - count;
+  }
+}
+
+void nsTreeContentView::SerializeItem(Element* aContent, int32_t aParentIndex,
+                                      int32_t* aIndex,
+                                      nsTArray<UniquePtr<Row>>& aRows) {
+  if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::hidden,
+                            nsGkAtoms::_true, eCaseMatters))
+    return;
+
+  aRows.AppendElement(MakeUnique<Row>(aContent, aParentIndex));
+  Row* row = aRows.LastElement().get();
+
+  if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::container,
+                            nsGkAtoms::_true, eCaseMatters)) {
+    row->SetContainer(true);
+    if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::open,
+                              nsGkAtoms::_true, eCaseMatters)) {
+      row->SetOpen(true);
+      nsIContent* child =
+          nsTreeUtils::GetImmediateChild(aContent, nsGkAtoms::treechildren);
+      if (child && child->IsXULElement()) {
+        // Now, recursively serialize our child.
+        int32_t count = aRows.Length();
+        int32_t index = 0;
+        Serialize(child, aParentIndex + *aIndex + 1, &index, aRows);
+        row->mSubtreeSize += aRows.Length() - count;
+      } else
+        row->SetEmpty(true);
+    } else if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::empty,
+                                     nsGkAtoms::_true, eCaseMatters)) {
+      row->SetEmpty(true);
+    }
+  }
+}
+
+void nsTreeContentView::SerializeSeparator(Element* aContent,
+                                           int32_t aParentIndex,
+                                           int32_t* aIndex,
+                                           nsTArray<UniquePtr<Row>>& aRows) {
+  if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::hidden,
+                            nsGkAtoms::_true, eCaseMatters))
+    return;
+
+  auto row = MakeUnique<Row>(aContent, aParentIndex);
+  row->SetSeparator(true);
+  aRows.AppendElement(std::move(row));
+}
+
+void nsTreeContentView::GetIndexInSubtree(nsIContent* aContainer,
+                                          nsIContent* aContent,
+                                          int32_t* aIndex) {
+  if (!aContainer->IsXULElement()) return;
+
+  for (nsIContent* content = aContainer->GetFirstChild(); content;
+       content = content->GetNextSibling()) {
+    if (content == aContent) break;
+
+    if (content->IsXULElement(nsGkAtoms::treeitem)) {
+      if (!content->AsElement()->AttrValueIs(kNameSpaceID_None,
+                                             nsGkAtoms::hidden,
+                                             nsGkAtoms::_true, eCaseMatters)) {
+        (*aIndex)++;
+        if (content->AsElement()->AttrValueIs(kNameSpaceID_None,
+                                              nsGkAtoms::container,
+                                              nsGkAtoms::_true, eCaseMatters) &&
+            content->AsElement()->AttrValueIs(kNameSpaceID_None,
+                                              nsGkAtoms::open, nsGkAtoms::_true,
+                                              eCaseMatters)) {
+          nsIContent* child =
+              nsTreeUtils::GetImmediateChild(content, nsGkAtoms::treechildren);
+          if (child && child->IsXULElement())
+            GetIndexInSubtree(child, aContent, aIndex);
+        }
+      }
+    } else if (content->IsXULElement(nsGkAtoms::treeseparator)) {
+      if (!content->AsElement()->AttrValueIs(kNameSpaceID_None,
+                                             nsGkAtoms::hidden,
+                                             nsGkAtoms::_true, eCaseMatters))
+        (*aIndex)++;
+    }
+  }
+}
+
+int32_t nsTreeContentView::EnsureSubtree(int32_t aIndex) {
+  Row* row = mRows[aIndex].get();
+
+  nsIContent* child;
+  child =
+      nsTreeUtils::GetImmediateChild(row->mContent, nsGkAtoms::treechildren);
+  if (!child || !child->IsXULElement()) {
+    return 0;
+  }
+
+  AutoTArray<UniquePtr<Row>, 8> rows;
+  int32_t index = 0;
+  Serialize(child, aIndex, &index, rows);
+  // Insert |rows| into |mRows| at position |aIndex|, by first creating empty
+  // UniquePtr entries and then Move'ing |rows|'s entries into them. (Note
+  // that we can't simply use InsertElementsAt with an array argument, since
+  // the destination can't steal ownership from its const source argument.)
+  UniquePtr<Row>* newRows = mRows.InsertElementsAt(aIndex + 1, rows.Length());
+  for (nsTArray<Row>::index_type i = 0; i < rows.Length(); i++) {
+    newRows[i] = std::move(rows[i]);
+  }
+  int32_t count = rows.Length();
+
+  row->mSubtreeSize += count;
+  UpdateSubtreeSizes(row->mParentIndex, count);
+
+  // Update parent indexes, but skip newly added rows.
+  // They already have correct values.
+  UpdateParentIndexes(aIndex, count + 1, count);
+
+  return count;
+}
+
+int32_t nsTreeContentView::RemoveSubtree(int32_t aIndex) {
+  Row* row = mRows[aIndex].get();
+  int32_t count = row->mSubtreeSize;
+
+  mRows.RemoveElementsAt(aIndex + 1, count);
+
+  row->mSubtreeSize -= count;
+  UpdateSubtreeSizes(row->mParentIndex, -count);
+
+  UpdateParentIndexes(aIndex, 0, -count);
+
+  return count;
+}
+
+void nsTreeContentView::InsertRowFor(nsIContent* aParent, nsIContent* aChild) {
+  int32_t grandParentIndex = -1;
+  bool insertRow = false;
+
+  nsCOMPtr<nsIContent> grandParent = aParent->GetParent();
+
+  if (grandParent->IsXULElement(nsGkAtoms::tree)) {
+    // Allow insertion to the outermost container.
+    insertRow = true;
+  } else {
+    // Test insertion to an inner container.
+
+    // First try to find this parent in our array of rows, if we find one
+    // we can be sure that all other parents are open too.
+    grandParentIndex = FindContent(grandParent);
+    if (grandParentIndex >= 0) {
+      // Got it, now test if it is open.
+      if (mRows[grandParentIndex]->IsOpen()) insertRow = true;
+    }
+  }
+
+  if (insertRow) {
+    int32_t index = 0;
+    GetIndexInSubtree(aParent, aChild, &index);
+
+    int32_t count = InsertRow(grandParentIndex, index, aChild);
+    if (mTree) mTree->RowCountChanged(grandParentIndex + index + 1, count);
+  }
+}
+
+int32_t nsTreeContentView::InsertRow(int32_t aParentIndex, int32_t aIndex,
+                                     nsIContent* aContent) {
+  AutoTArray<UniquePtr<Row>, 8> rows;
+  if (aContent->IsXULElement(nsGkAtoms::treeitem)) {
+    SerializeItem(aContent->AsElement(), aParentIndex, &aIndex, rows);
+  } else if (aContent->IsXULElement(nsGkAtoms::treeseparator)) {
+    SerializeSeparator(aContent->AsElement(), aParentIndex, &aIndex, rows);
+  }
+
+  // We can't use InsertElementsAt since the destination can't steal
+  // ownership from its const source argument.
+  int32_t count = rows.Length();
+  for (nsTArray<Row>::index_type i = 0; i < size_t(count); i++) {
+    mRows.InsertElementAt(aParentIndex + aIndex + i + 1, std::move(rows[i]));
+  }
+
+  UpdateSubtreeSizes(aParentIndex, count);
+
+  // Update parent indexes, but skip added rows.
+  // They already have correct values.
+  UpdateParentIndexes(aParentIndex + aIndex, count + 1, count);
+
+  return count;
+}
+
+int32_t nsTreeContentView::RemoveRow(int32_t aIndex) {
+  Row* row = mRows[aIndex].get();
+  int32_t count = row->mSubtreeSize + 1;
+  int32_t parentIndex = row->mParentIndex;
+
+  mRows.RemoveElementsAt(aIndex, count);
+
+  UpdateSubtreeSizes(parentIndex, -count);
+
+  UpdateParentIndexes(aIndex, 0, -count);
+
+  return count;
+}
+
+void nsTreeContentView::ClearRows() {
+  mRows.Clear();
+  mBody = nullptr;
+  // Remove ourselves from mDocument's observers.
+  if (mDocument) {
+    mDocument->RemoveObserver(this);
+    mDocument = nullptr;
+  }
+}
+
+void nsTreeContentView::OpenContainer(int32_t aIndex) {
+  Row* row = mRows[aIndex].get();
+  row->SetOpen(true);
+
+  int32_t count = EnsureSubtree(aIndex);
+  if (mTree) {
+    mTree->InvalidateRow(aIndex);
+    mTree->RowCountChanged(aIndex + 1, count);
+  }
+}
+
+void nsTreeContentView::CloseContainer(int32_t aIndex) {
+  Row* row = mRows[aIndex].get();
+  row->SetOpen(false);
+
+  int32_t count = RemoveSubtree(aIndex);
+  if (mTree) {
+    mTree->InvalidateRow(aIndex);
+    mTree->RowCountChanged(aIndex + 1, -count);
+  }
+}
+
+int32_t nsTreeContentView::FindContent(nsIContent* aContent) {
+  for (uint32_t i = 0; i < mRows.Length(); i++) {
+    if (mRows[i]->mContent == aContent) {
+      return i;
+    }
+  }
+
+  return -1;
+}
+
+void nsTreeContentView::UpdateSubtreeSizes(int32_t aParentIndex,
+                                           int32_t count) {
+  while (aParentIndex >= 0) {
+    Row* row = mRows[aParentIndex].get();
+    row->mSubtreeSize += count;
+    aParentIndex = row->mParentIndex;
+  }
+}
+
+void nsTreeContentView::UpdateParentIndexes(int32_t aIndex, int32_t aSkip,
+                                            int32_t aCount) {
+  int32_t count = mRows.Length();
+  for (int32_t i = aIndex + aSkip; i < count; i++) {
+    Row* row = mRows[i].get();
+    if (row->mParentIndex > aIndex) {
+      row->mParentIndex += aCount;
+    }
+  }
+}
+
+Element* nsTreeContentView::GetCell(nsIContent* aContainer,
+                                    nsTreeColumn& aCol) {
+  int32_t colIndex(aCol.GetIndex());
+
+  // Traverse through cells, try to find the cell by index in a row.
+  Element* result = nullptr;
+  int32_t j = 0;
+  dom::FlattenedChildIterator iter(aContainer);
+  for (nsIContent* cell = iter.GetNextChild(); cell;
+       cell = iter.GetNextChild()) {
+    if (cell->IsXULElement(nsGkAtoms::treecell)) {
+      if (j == colIndex) {
+        result = cell->AsElement();
+        break;
+      }
+      j++;
+    }
+  }
+
+  return result;
+}
+
+bool nsTreeContentView::IsValidRowIndex(int32_t aRowIndex) {
+  return aRowIndex >= 0 && aRowIndex < int32_t(mRows.Length());
+}