Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 607 insertions, 0 deletions

diff --git a/layout/xul/tree/nsTreeBodyFrame.h b/layout/xul/tree/nsTreeBodyFrame.h
new file mode 100644
index 0000000000..dd38644ad9
--- /dev/null
+++ b/layout/xul/tree/nsTreeBodyFrame.h
@@ -0,0 +1,607 @@
+/* -*- 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/. */
+
+#ifndef nsTreeBodyFrame_h
+#define nsTreeBodyFrame_h
+
+#include "mozilla/AtomArray.h"
+#include "mozilla/Attributes.h"
+
+#include "nsITreeView.h"
+#include "nsIScrollbarMediator.h"
+#include "nsITimer.h"
+#include "nsIReflowCallback.h"
+#include "nsTArray.h"
+#include "nsTreeStyleCache.h"
+#include "nsTreeColumns.h"
+#include "nsTHashMap.h"
+#include "nsTHashSet.h"
+#include "imgIRequest.h"
+#include "imgINotificationObserver.h"
+#include "nsScrollbarFrame.h"
+#include "nsThreadUtils.h"
+#include "SimpleXULLeafFrame.h"
+#include "mozilla/LookAndFeel.h"
+
+class nsFontMetrics;
+class nsOverflowChecker;
+class nsTreeImageListener;
+
+namespace mozilla {
+class PresShell;
+namespace layout {
+class ScrollbarActivity;
+}  // namespace layout
+}  // namespace mozilla
+
+// An entry in the tree's image cache
+struct nsTreeImageCacheEntry {
+  nsTreeImageCacheEntry() = default;
+  nsTreeImageCacheEntry(imgIRequest* aRequest,
+                        imgINotificationObserver* aListener)
+      : request(aRequest), listener(aListener) {}
+
+  nsCOMPtr<imgIRequest> request;
+  nsCOMPtr<imgINotificationObserver> listener;
+};
+
+// The actual frame that paints the cells and rows.
+class nsTreeBodyFrame final : public mozilla::SimpleXULLeafFrame,
+                              public nsIScrollbarMediator,
+                              public nsIReflowCallback {
+  typedef mozilla::layout::ScrollbarActivity ScrollbarActivity;
+  typedef mozilla::image::ImgDrawResult ImgDrawResult;
+
+ public:
+  explicit nsTreeBodyFrame(ComputedStyle* aStyle, nsPresContext* aPresContext);
+  ~nsTreeBodyFrame();
+
+  nscoord GetIntrinsicBSize() override;
+
+  NS_DECL_QUERYFRAME
+  NS_DECL_FRAMEARENA_HELPERS(nsTreeBodyFrame)
+
+  // Callback handler methods for refresh driver based animations.
+  // Calls to these functions are forwarded from nsTreeImageListener. These
+  // mirror how nsImageFrame works.
+  void OnImageIsAnimated(imgIRequest* aRequest);
+
+  // non-virtual signatures like nsITreeBodyFrame
+  already_AddRefed<nsTreeColumns> Columns() const {
+    RefPtr<nsTreeColumns> cols = mColumns;
+    return cols.forget();
+  }
+  already_AddRefed<nsITreeView> GetExistingView() const {
+    nsCOMPtr<nsITreeView> view = mView;
+    return view.forget();
+  }
+  already_AddRefed<nsITreeSelection> GetSelection() const;
+  nsresult GetView(nsITreeView** aView);
+  nsresult SetView(nsITreeView* aView);
+  bool GetFocused() const { return mFocused; }
+  nsresult SetFocused(bool aFocused);
+  nsresult GetTreeBody(mozilla::dom::Element** aElement);
+  int32_t RowHeight() const;
+  int32_t RowWidth();
+  int32_t GetHorizontalPosition() const;
+  mozilla::Maybe<mozilla::CSSIntRegion> GetSelectionRegion();
+  int32_t FirstVisibleRow() const { return mTopRowIndex; }
+  int32_t LastVisibleRow() const { return mTopRowIndex + mPageLength; }
+  int32_t PageLength() const { return mPageLength; }
+  nsresult EnsureRowIsVisible(int32_t aRow);
+  nsresult EnsureCellIsVisible(int32_t aRow, nsTreeColumn* aCol);
+  void ScrollToRow(int32_t aRow);
+  void ScrollByLines(int32_t aNumLines);
+  void ScrollByPages(int32_t aNumPages);
+  nsresult Invalidate();
+  nsresult InvalidateColumn(nsTreeColumn* aCol);
+  nsresult InvalidateRow(int32_t aRow);
+  nsresult InvalidateCell(int32_t aRow, nsTreeColumn* aCol);
+  nsresult InvalidateRange(int32_t aStart, int32_t aEnd);
+  int32_t GetRowAt(int32_t aX, int32_t aY);
+  nsresult GetCellAt(int32_t aX, int32_t aY, int32_t* aRow, nsTreeColumn** aCol,
+                     nsACString& aChildElt);
+  nsresult GetCoordsForCellItem(int32_t aRow, nsTreeColumn* aCol,
+                                const nsACString& aElt, int32_t* aX,
+                                int32_t* aY, int32_t* aWidth, int32_t* aHeight);
+  nsresult IsCellCropped(int32_t aRow, nsTreeColumn* aCol, bool* aResult);
+  nsresult RowCountChanged(int32_t aIndex, int32_t aCount);
+  nsresult BeginUpdateBatch();
+  nsresult EndUpdateBatch();
+  nsresult ClearStyleAndImageCaches();
+  void RemoveImageCacheEntry(int32_t aRowIndex, nsTreeColumn* aCol);
+
+  void CancelImageRequests();
+
+  void ManageReflowCallback();
+
+  void DidReflow(nsPresContext*, const ReflowInput*) override;
+
+  // nsIReflowCallback
+  bool ReflowFinished() override;
+  void ReflowCallbackCanceled() override;
+
+  // nsIScrollbarMediator
+  void ScrollByPage(nsScrollbarFrame* aScrollbar, int32_t aDirection,
+                    mozilla::ScrollSnapFlags aSnapFlags =
+                        mozilla::ScrollSnapFlags::Disabled) override;
+  void ScrollByWhole(nsScrollbarFrame* aScrollbar, int32_t aDirection,
+                     mozilla::ScrollSnapFlags aSnapFlags =
+                         mozilla::ScrollSnapFlags::Disabled) override;
+  void ScrollByLine(nsScrollbarFrame* aScrollbar, int32_t aDirection,
+                    mozilla::ScrollSnapFlags aSnapFlags =
+                        mozilla::ScrollSnapFlags::Disabled) override;
+  void ScrollByUnit(nsScrollbarFrame* aScrollbar, mozilla::ScrollMode aMode,
+                    int32_t aDirection, mozilla::ScrollUnit aUnit,
+                    mozilla::ScrollSnapFlags aSnapFlags =
+                        mozilla::ScrollSnapFlags::Disabled) override;
+  void RepeatButtonScroll(nsScrollbarFrame* aScrollbar) override;
+  void ThumbMoved(nsScrollbarFrame* aScrollbar, nscoord aOldPos,
+                  nscoord aNewPos) override;
+  void ScrollbarReleased(nsScrollbarFrame* aScrollbar) override {}
+  void VisibilityChanged(bool aVisible) override { Invalidate(); }
+  nsScrollbarFrame* GetScrollbarBox(bool aVertical) override {
+    ScrollParts parts = GetScrollParts();
+    return aVertical ? parts.mVScrollbar : parts.mHScrollbar;
+  }
+  void ScrollbarActivityStarted() const override;
+  void ScrollbarActivityStopped() const override;
+  bool IsScrollbarOnRight() const override {
+    return StyleVisibility()->mDirection == mozilla::StyleDirection::Ltr;
+  }
+  bool ShouldSuppressScrollbarRepaints() const override { return false; }
+
+  // Overridden from nsIFrame to cache our pres context.
+  void Init(nsIContent* aContent, nsContainerFrame* aParent,
+            nsIFrame* aPrevInFlow) override;
+  void Destroy(DestroyContext&) override;
+
+  Cursor GetCursor(const nsPoint&) override;
+
+  nsresult HandleEvent(nsPresContext* aPresContext,
+                       mozilla::WidgetGUIEvent* aEvent,
+                       nsEventStatus* aEventStatus) override;
+
+  void BuildDisplayList(nsDisplayListBuilder* aBuilder,
+                        const nsDisplayListSet& aLists) override;
+
+  void DidSetComputedStyle(ComputedStyle* aOldComputedStyle) override;
+
+  friend nsIFrame* NS_NewTreeBodyFrame(mozilla::PresShell* aPresShell);
+  friend class nsTreeColumn;
+
+  struct ScrollParts {
+    nsScrollbarFrame* mVScrollbar;
+    RefPtr<mozilla::dom::Element> mVScrollbarContent;
+    nsScrollbarFrame* mHScrollbar;
+    RefPtr<mozilla::dom::Element> mHScrollbarContent;
+    nsIFrame* mColumnsFrame;
+    nsIScrollableFrame* mColumnsScrollFrame;
+  };
+
+  ImgDrawResult PaintTreeBody(gfxContext& aRenderingContext,
+                              const nsRect& aDirtyRect, nsPoint aPt,
+                              nsDisplayListBuilder* aBuilder);
+
+  // Get the base element, <tree>
+  mozilla::dom::XULTreeElement* GetBaseElement();
+
+  bool GetVerticalOverflow() const { return mVerticalOverflow; }
+  bool GetHorizontalOverflow() const { return mHorizontalOverflow; }
+
+  // This returns the property array where atoms are stored for style during
+  // draw, whether the row currently being drawn is selected, hovered, etc.
+  const mozilla::AtomArray& GetPropertyArrayForCurrentDrawingItem() {
+    return mScratchArray;
+  }
+
+ protected:
+  friend class nsOverflowChecker;
+
+  // This method paints a specific column background of the tree.
+  ImgDrawResult PaintColumn(nsTreeColumn* aColumn, const nsRect& aColumnRect,
+                            nsPresContext* aPresContext,
+                            gfxContext& aRenderingContext,
+                            const nsRect& aDirtyRect);
+
+  // This method paints a single row in the tree.
+  ImgDrawResult PaintRow(int32_t aRowIndex, const nsRect& aRowRect,
+                         nsPresContext* aPresContext,
+                         gfxContext& aRenderingContext,
+                         const nsRect& aDirtyRect, nsPoint aPt,
+                         nsDisplayListBuilder* aBuilder);
+
+  // This method paints a single separator in the tree.
+  ImgDrawResult PaintSeparator(int32_t aRowIndex, const nsRect& aSeparatorRect,
+                               nsPresContext* aPresContext,
+                               gfxContext& aRenderingContext,
+                               const nsRect& aDirtyRect);
+
+  // This method paints a specific cell in a given row of the tree.
+  ImgDrawResult PaintCell(int32_t aRowIndex, nsTreeColumn* aColumn,
+                          const nsRect& aCellRect, nsPresContext* aPresContext,
+                          gfxContext& aRenderingContext,
+                          const nsRect& aDirtyRect, nscoord& aCurrX,
+                          nsPoint aPt, nsDisplayListBuilder* aBuilder);
+
+  // This method paints the twisty inside a cell in the primary column of an
+  // tree.
+  ImgDrawResult PaintTwisty(int32_t aRowIndex, nsTreeColumn* aColumn,
+                            const nsRect& aTwistyRect,
+                            nsPresContext* aPresContext,
+                            gfxContext& aRenderingContext,
+                            const nsRect& aDirtyRect, nscoord& aRemainingWidth,
+                            nscoord& aCurrX);
+
+  // This method paints the image inside the cell of an tree.
+  ImgDrawResult PaintImage(int32_t aRowIndex, nsTreeColumn* aColumn,
+                           const nsRect& aImageRect,
+                           nsPresContext* aPresContext,
+                           gfxContext& aRenderingContext,
+                           const nsRect& aDirtyRect, nscoord& aRemainingWidth,
+                           nscoord& aCurrX, nsDisplayListBuilder* aBuilder);
+
+  // This method paints the text string inside a particular cell of the tree.
+  ImgDrawResult PaintText(int32_t aRowIndex, nsTreeColumn* aColumn,
+                          const nsRect& aTextRect, nsPresContext* aPresContext,
+                          gfxContext& aRenderingContext,
+                          const nsRect& aDirtyRect, nscoord& aCurrX);
+
+  // This method paints the checkbox inside a particular cell of the tree.
+  ImgDrawResult PaintCheckbox(int32_t aRowIndex, nsTreeColumn* aColumn,
+                              const nsRect& aCheckboxRect,
+                              nsPresContext* aPresContext,
+                              gfxContext& aRenderingContext,
+                              const nsRect& aDirtyRect);
+
+  // This method paints a drop feedback of the tree.
+  ImgDrawResult PaintDropFeedback(const nsRect& aDropFeedbackRect,
+                                  nsPresContext* aPresContext,
+                                  gfxContext& aRenderingContext,
+                                  const nsRect& aDirtyRect, nsPoint aPt);
+
+  // This method is called with a specific ComputedStyle and rect to
+  // paint the background rect as if it were a full-blown frame.
+  ImgDrawResult PaintBackgroundLayer(ComputedStyle* aComputedStyle,
+                                     nsPresContext* aPresContext,
+                                     gfxContext& aRenderingContext,
+                                     const nsRect& aRect,
+                                     const nsRect& aDirtyRect);
+
+  // An internal hit test.  aX and aY are expected to be in twips in the
+  // coordinate system of this frame.
+  int32_t GetRowAtInternal(nscoord aX, nscoord aY);
+
+  // Check for bidi characters in the text, and if there are any, ensure
+  // that the prescontext is in bidi mode.
+  void CheckTextForBidi(nsAutoString& aText);
+
+  void AdjustForCellText(nsAutoString& aText, int32_t aRowIndex,
+                         nsTreeColumn* aColumn, gfxContext& aRenderingContext,
+                         nsFontMetrics& aFontMetrics, nsRect& aTextRect);
+
+  // A helper used when hit testing.
+  nsCSSAnonBoxPseudoStaticAtom* GetItemWithinCellAt(nscoord aX,
+                                                    const nsRect& aCellRect,
+                                                    int32_t aRowIndex,
+                                                    nsTreeColumn* aColumn);
+
+  // An internal hit test.  aX and aY are expected to be in twips in the
+  // coordinate system of this frame.
+  void GetCellAt(nscoord aX, nscoord aY, int32_t* aRow, nsTreeColumn** aCol,
+                 nsCSSAnonBoxPseudoStaticAtom** aChildElt);
+
+  // Retrieve the area for the twisty for a cell.
+  nsITheme* GetTwistyRect(int32_t aRowIndex, nsTreeColumn* aColumn,
+                          nsRect& aImageRect, nsRect& aTwistyRect,
+                          nsPresContext* aPresContext,
+                          ComputedStyle* aTwistyContext);
+
+  // Fetch an image from the image cache.
+  nsresult GetImage(int32_t aRowIndex, nsTreeColumn* aCol, bool aUseContext,
+                    ComputedStyle* aComputedStyle, imgIContainer** aResult);
+
+  // Returns the size of a given image.   This size *includes* border and
+  // padding.  It does not include margins.
+  nsRect GetImageSize(int32_t aRowIndex, nsTreeColumn* aCol, bool aUseContext,
+                      ComputedStyle* aComputedStyle);
+
+  // Returns the destination size of the image, not including borders and
+  // padding.
+  nsSize GetImageDestSize(ComputedStyle*, imgIContainer*);
+
+  // Returns the source rectangle of the image to be displayed.
+  nsRect GetImageSourceRect(ComputedStyle*, imgIContainer*);
+
+  // Returns the height of rows in the tree.
+  int32_t GetRowHeight();
+
+  // Returns our indentation width.
+  int32_t GetIndentation();
+
+  // Calculates our width/height once border and padding have been removed.
+  void CalcInnerBox();
+
+  // Calculate the total width of our scrollable portion
+  nscoord CalcHorzWidth(const ScrollParts& aParts);
+
+  // Looks up a ComputedStyle in the style cache.  On a cache miss we resolve
+  // the pseudo-styles passed in and place them into the cache.
+  ComputedStyle* GetPseudoComputedStyle(
+      nsCSSAnonBoxPseudoStaticAtom* aPseudoElement);
+
+  // Retrieves the scrollbars and scrollview relevant to this treebody. We
+  // traverse the frame tree under our base element, in frame order, looking
+  // for the first relevant vertical scrollbar, horizontal scrollbar, and
+  // scrollable frame (with associated content and scrollable view). These
+  // are all volatile and should not be retained.
+  ScrollParts GetScrollParts();
+
+  // Update the curpos of the scrollbar.
+  void UpdateScrollbars(const ScrollParts& aParts);
+
+  // Update the maxpos of the scrollbar.
+  void InvalidateScrollbars(const ScrollParts& aParts,
+                            AutoWeakFrame& aWeakColumnsFrame);
+
+  // Check overflow and generate events.
+  MOZ_CAN_RUN_SCRIPT_BOUNDARY void CheckOverflow(const ScrollParts& aParts);
+
+  // Calls UpdateScrollbars, Invalidate aNeedsFullInvalidation if true,
+  // InvalidateScrollbars and finally CheckOverflow.
+  // returns true if the frame is still alive after the method call.
+  bool FullScrollbarsUpdate(bool aNeedsFullInvalidation);
+
+  // Use to auto-fill some of the common properties without the view having to
+  // do it. Examples include container, open, selected, and focus.
+  void PrefillPropertyArray(int32_t aRowIndex, nsTreeColumn* aCol);
+
+  // Our internal scroll method, used by all the public scroll methods.
+  nsresult ScrollInternal(const ScrollParts& aParts, int32_t aRow);
+  nsresult ScrollToRowInternal(const ScrollParts& aParts, int32_t aRow);
+  nsresult ScrollHorzInternal(const ScrollParts& aParts, int32_t aPosition);
+  nsresult EnsureRowIsVisibleInternal(const ScrollParts& aParts, int32_t aRow);
+
+  // Convert client pixels into appunits in our coordinate space.
+  nsPoint AdjustClientCoordsToBoxCoordSpace(int32_t aX, int32_t aY);
+
+  void EnsureView();
+
+  nsresult GetCellWidth(int32_t aRow, nsTreeColumn* aCol,
+                        gfxContext* aRenderingContext, nscoord& aDesiredSize,
+                        nscoord& aCurrentSize);
+
+  // Translate the given rect horizontally from tree coordinates into the
+  // coordinate system of our nsTreeBodyFrame.  If clip is true, then clip the
+  // rect to its intersection with mInnerBox in the horizontal direction.
+  // Return whether the result has a nonempty intersection with mInnerBox
+  // after projecting both onto the horizontal coordinate axis.
+  bool OffsetForHorzScroll(nsRect& rect, bool clip);
+
+  bool CanAutoScroll(int32_t aRowIndex);
+
+  // Calc the row and above/below/on status given where the mouse currently is
+  // hovering. Also calc if we're in the region in which we want to auto-scroll
+  // the tree. A positive value of |aScrollLines| means scroll down, a negative
+  // value means scroll up, a zero value means that we aren't in drag scroll
+  // region.
+  void ComputeDropPosition(mozilla::WidgetGUIEvent* aEvent, int32_t* aRow,
+                           int16_t* aOrient, int16_t* aScrollLines);
+
+  void InvalidateDropFeedback(int32_t aRow, int16_t aOrientation) {
+    InvalidateRow(aRow);
+    if (aOrientation != nsITreeView::DROP_ON)
+      InvalidateRow(aRow + aOrientation);
+  }
+
+ public:
+  /**
+   * Remove an nsITreeImageListener from being tracked by this frame. Only tree
+   * image listeners that are created by this frame are tracked.
+   *
+   * @param aListener A pointer to an nsTreeImageListener to no longer
+   *        track.
+   */
+  void RemoveTreeImageListener(nsTreeImageListener* aListener);
+
+ protected:
+  // Create a new timer. This method is used to delay various actions like
+  // opening/closing folders or tree scrolling.
+  // aID is type of the action, aFunc is the function to be called when
+  // the timer fires and aType is type of timer - one shot or repeating.
+  nsresult CreateTimer(const mozilla::LookAndFeel::IntID aID,
+                       nsTimerCallbackFunc aFunc, int32_t aType,
+                       nsITimer** aTimer, const char* aName);
+
+  static void OpenCallback(nsITimer* aTimer, void* aClosure);
+
+  static void CloseCallback(nsITimer* aTimer, void* aClosure);
+
+  static void LazyScrollCallback(nsITimer* aTimer, void* aClosure);
+
+  static void ScrollCallback(nsITimer* aTimer, void* aClosure);
+
+  class ScrollEvent : public mozilla::Runnable {
+   public:
+    NS_DECL_NSIRUNNABLE
+    explicit ScrollEvent(nsTreeBodyFrame* aInner)
+        : mozilla::Runnable("nsTreeBodyFrame::ScrollEvent"), mInner(aInner) {}
+    void Revoke() { mInner = nullptr; }
+
+   private:
+    nsTreeBodyFrame* mInner;
+  };
+
+  void PostScrollEvent();
+  MOZ_CAN_RUN_SCRIPT void FireScrollEvent();
+
+  /**
+   * Clear the pointer to this frame for all nsTreeImageListeners that were
+   * created by this frame.
+   */
+  void DetachImageListeners();
+
+#ifdef ACCESSIBILITY
+  /**
+   * Fires 'treeRowCountChanged' event asynchronously. The event is a
+   * CustomEvent that is used to expose the following information structures
+   * via a property bag.
+   *
+   * @param aIndex  the row index rows are added/removed from
+   * @param aCount  the number of added/removed rows (the sign points to
+   *                an operation, plus - addition, minus - removing)
+   */
+  void FireRowCountChangedEvent(int32_t aIndex, int32_t aCount);
+
+  /**
+   * Fires 'treeInvalidated' event asynchronously. The event is a CustomEvent
+   * that is used to expose the information structures described by method
+   * arguments via a property bag.
+   *
+   * @param aStartRow  the start index of invalidated rows, -1 means that
+   *                   columns have been invalidated only
+   * @param aEndRow    the end index of invalidated rows, -1 means that columns
+   *                   have been invalidated only
+   * @param aStartCol  the start invalidated column, nullptr means that only
+   *                   rows have been invalidated
+   * @param aEndCol    the end invalidated column, nullptr means that rows have
+   *                   been invalidated only
+   */
+  void FireInvalidateEvent(int32_t aStartRow, int32_t aEndRow,
+                           nsTreeColumn* aStartCol, nsTreeColumn* aEndCol);
+#endif
+
+ protected:  // Data Members
+  class Slots {
+   public:
+    Slots() = default;
+
+    ~Slots() {
+      if (mTimer) {
+        mTimer->Cancel();
+      }
+    }
+
+    friend class nsTreeBodyFrame;
+
+   protected:
+    // If the drop is actually allowed here or not.
+    bool mDropAllowed = false;
+
+    // True while dragging over the tree.
+    bool mIsDragging = false;
+
+    // The row the mouse is hovering over during a drop.
+    int32_t mDropRow = -1;
+
+    // Where we want to draw feedback (above/on this row/below) if allowed.
+    int16_t mDropOrient = -1;
+
+    // Number of lines to be scrolled.
+    int16_t mScrollLines = 0;
+
+    // The drag action that was received for this slot
+    uint32_t mDragAction = 0;
+
+    // Timer for opening/closing spring loaded folders or scrolling the tree.
+    nsCOMPtr<nsITimer> mTimer;
+
+    // An array used to keep track of all spring loaded folders.
+    nsTArray<int32_t> mArray;
+  };
+
+  mozilla::UniquePtr<Slots> mSlots;
+
+  nsRevocableEventPtr<ScrollEvent> mScrollEvent;
+
+  RefPtr<ScrollbarActivity> mScrollbarActivity;
+
+  // The <tree> element containing this treebody.
+  RefPtr<mozilla::dom::XULTreeElement> mTree;
+
+  // Cached column information.
+  RefPtr<nsTreeColumns> mColumns;
+
+  // The current view for this tree widget.  We get all of our row and cell data
+  // from the view.
+  nsCOMPtr<nsITreeView> mView;
+
+  // A cache of all the ComputedStyles we have seen for rows and cells of the
+  // tree.  This is a mapping from a list of atoms to a corresponding
+  // ComputedStyle.  This cache stores every combination that occurs in the
+  // tree, so for n distinct properties, this cache could have 2 to the n
+  // entries (the power set of all row properties).
+  nsTreeStyleCache mStyleCache;
+
+  // A hashtable that maps from URLs to image request/listener pairs.  The URL
+  // is provided by the view or by the ComputedStyle. The ComputedStyle
+  // represents a resolved :-moz-tree-cell-image (or twisty) pseudo-element.
+  // It maps directly to an imgIRequest.
+  nsTHashMap<nsStringHashKey, nsTreeImageCacheEntry> mImageCache;
+
+  // A scratch array used when looking up cached ComputedStyles.
+  mozilla::AtomArray mScratchArray;
+
+  // The index of the first visible row and the # of rows visible onscreen.
+  // The tree only examines onscreen rows, starting from
+  // this index and going up to index+pageLength.
+  int32_t mTopRowIndex;
+  int32_t mPageLength;
+
+  // The horizontal scroll position
+  nscoord mHorzPosition;
+
+  // The original desired horizontal width before changing it and posting a
+  // reflow callback. In some cases, the desired horizontal width can first be
+  // different from the current desired horizontal width, only to return to
+  // the same value later during the same reflow. In this case, we can cancel
+  // the posted reflow callback and prevent an unnecessary reflow.
+  nscoord mOriginalHorzWidth;
+  // Our desired horizontal width (the width for which we actually have tree
+  // columns).
+  nscoord mHorzWidth;
+  // The amount by which to adjust the width of the last cell.
+  // This depends on whether or not the columnpicker and scrollbars are present.
+  nscoord mAdjustWidth;
+
+  // Our last reflowed rect, used for invalidation, see ManageReflowCallback().
+  Maybe<nsRect> mLastReflowRect;
+
+  // Cached heights and indent info.
+  nsRect mInnerBox;  // 4-byte aligned
+  int32_t mRowHeight;
+  int32_t mIndentation;
+
+  int32_t mUpdateBatchNest;
+
+  // Cached row count.
+  int32_t mRowCount;
+
+  // The row the mouse is hovering over.
+  int32_t mMouseOverRow;
+
+  // Whether or not we're currently focused.
+  bool mFocused;
+
+  // Do we have a fixed number of onscreen rows?
+  bool mHasFixedRowCount;
+
+  bool mVerticalOverflow;
+  bool mHorizontalOverflow;
+
+  bool mReflowCallbackPosted;
+
+  // Set while we flush layout to take account of effects of
+  // overflow/underflow event handlers
+  bool mCheckingOverflow;
+
+  // Hash set to keep track of which listeners we created and thus
+  // have pointers to us.
+  nsTHashSet<nsTreeImageListener*> mCreatedListeners;
+
+};  // class nsTreeBodyFrame
+
+#endif