Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

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

1 files changed, 1131 insertions, 0 deletions

diff --git a/docshell/shistory/nsSHEntry.cpp b/docshell/shistory/nsSHEntry.cpp
new file mode 100644
index 0000000000..0b250c33ff
--- /dev/null
+++ b/docshell/shistory/nsSHEntry.cpp
@@ -0,0 +1,1131 @@
+/* -*- 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 "nsSHEntry.h"
+
+#include <algorithm>
+
+#include "nsDocShell.h"
+#include "nsDocShellEditorData.h"
+#include "nsDocShellLoadState.h"
+#include "nsDocShellLoadTypes.h"
+#include "nsIContentSecurityPolicy.h"
+#include "nsIContentViewer.h"
+#include "nsIDocShellTreeItem.h"
+#include "nsIInputStream.h"
+#include "nsILayoutHistoryState.h"
+#include "nsIMutableArray.h"
+#include "nsIStructuredCloneContainer.h"
+#include "nsIURI.h"
+#include "nsSHEntryShared.h"
+#include "nsSHistory.h"
+
+#include "mozilla/Logging.h"
+#include "nsIReferrerInfo.h"
+
+extern mozilla::LazyLogModule gPageCacheLog;
+
+static uint32_t gEntryID = 0;
+
+nsSHEntry::nsSHEntry()
+    : mShared(new nsSHEntryShared()),
+      mLoadType(0),
+      mID(++gEntryID),  // SessionStore has special handling for 0 values.
+      mScrollPositionX(0),
+      mScrollPositionY(0),
+      mLoadReplace(false),
+      mURIWasModified(false),
+      mIsSrcdocEntry(false),
+      mScrollRestorationIsManual(false),
+      mLoadedInThisProcess(false),
+      mPersist(true),
+      mHasUserInteraction(false),
+      mHasUserActivation(false) {}
+
+nsSHEntry::nsSHEntry(const nsSHEntry& aOther)
+    : mShared(aOther.mShared),
+      mURI(aOther.mURI),
+      mOriginalURI(aOther.mOriginalURI),
+      mResultPrincipalURI(aOther.mResultPrincipalURI),
+      mUnstrippedURI(aOther.mUnstrippedURI),
+      mReferrerInfo(aOther.mReferrerInfo),
+      mTitle(aOther.mTitle),
+      mPostData(aOther.mPostData),
+      mLoadType(0),  // XXX why not copy?
+      mID(aOther.mID),
+      mScrollPositionX(0),  // XXX why not copy?
+      mScrollPositionY(0),  // XXX why not copy?
+      mParent(aOther.mParent),
+      mStateData(aOther.mStateData),
+      mSrcdocData(aOther.mSrcdocData),
+      mBaseURI(aOther.mBaseURI),
+      mLoadReplace(aOther.mLoadReplace),
+      mURIWasModified(aOther.mURIWasModified),
+      mIsSrcdocEntry(aOther.mIsSrcdocEntry),
+      mScrollRestorationIsManual(false),
+      mLoadedInThisProcess(aOther.mLoadedInThisProcess),
+      mPersist(aOther.mPersist),
+      mHasUserInteraction(false),
+      mHasUserActivation(aOther.mHasUserActivation) {}
+
+nsSHEntry::~nsSHEntry() {
+  // Null out the mParent pointers on all our kids.
+  for (nsISHEntry* entry : mChildren) {
+    if (entry) {
+      entry->SetParent(nullptr);
+    }
+  }
+}
+
+NS_IMPL_ISUPPORTS(nsSHEntry, nsISHEntry, nsISupportsWeakReference)
+
+NS_IMETHODIMP
+nsSHEntry::SetScrollPosition(int32_t aX, int32_t aY) {
+  mScrollPositionX = aX;
+  mScrollPositionY = aY;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetScrollPosition(int32_t* aX, int32_t* aY) {
+  *aX = mScrollPositionX;
+  *aY = mScrollPositionY;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetURIWasModified(bool* aOut) {
+  *aOut = mURIWasModified;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetURIWasModified(bool aIn) {
+  mURIWasModified = aIn;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetURI(nsIURI** aURI) {
+  *aURI = mURI;
+  NS_IF_ADDREF(*aURI);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetURI(nsIURI* aURI) {
+  mURI = aURI;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetOriginalURI(nsIURI** aOriginalURI) {
+  *aOriginalURI = mOriginalURI;
+  NS_IF_ADDREF(*aOriginalURI);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetOriginalURI(nsIURI* aOriginalURI) {
+  mOriginalURI = aOriginalURI;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetResultPrincipalURI(nsIURI** aResultPrincipalURI) {
+  *aResultPrincipalURI = mResultPrincipalURI;
+  NS_IF_ADDREF(*aResultPrincipalURI);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetResultPrincipalURI(nsIURI* aResultPrincipalURI) {
+  mResultPrincipalURI = aResultPrincipalURI;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetUnstrippedURI(nsIURI** aUnstrippedURI) {
+  *aUnstrippedURI = mUnstrippedURI;
+  NS_IF_ADDREF(*aUnstrippedURI);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetUnstrippedURI(nsIURI* aUnstrippedURI) {
+  mUnstrippedURI = aUnstrippedURI;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetLoadReplace(bool* aLoadReplace) {
+  *aLoadReplace = mLoadReplace;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetLoadReplace(bool aLoadReplace) {
+  mLoadReplace = aLoadReplace;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetReferrerInfo(nsIReferrerInfo** aReferrerInfo) {
+  *aReferrerInfo = mReferrerInfo;
+  NS_IF_ADDREF(*aReferrerInfo);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetReferrerInfo(nsIReferrerInfo* aReferrerInfo) {
+  mReferrerInfo = aReferrerInfo;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetSticky(bool aSticky) {
+  mShared->mSticky = aSticky;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetSticky(bool* aSticky) {
+  *aSticky = mShared->mSticky;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetTitle(nsAString& aTitle) {
+  // Check for empty title...
+  if (mTitle.IsEmpty() && mURI) {
+    // Default title is the URL.
+    nsAutoCString spec;
+    if (NS_SUCCEEDED(mURI->GetSpec(spec))) {
+      AppendUTF8toUTF16(spec, mTitle);
+    }
+  }
+
+  aTitle = mTitle;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetTitle(const nsAString& aTitle) {
+  mTitle = aTitle;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetName(nsAString& aName) {
+  aName = mName;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetName(const nsAString& aName) {
+  mName = aName;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetPostData(nsIInputStream** aResult) {
+  *aResult = mPostData;
+  NS_IF_ADDREF(*aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetPostData(nsIInputStream* aPostData) {
+  mPostData = aPostData;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetHasPostData(bool* aResult) {
+  *aResult = !!mPostData;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetLayoutHistoryState(nsILayoutHistoryState** aResult) {
+  *aResult = mShared->mLayoutHistoryState;
+  NS_IF_ADDREF(*aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetLayoutHistoryState(nsILayoutHistoryState* aState) {
+  mShared->mLayoutHistoryState = aState;
+  if (mShared->mLayoutHistoryState) {
+    mShared->mLayoutHistoryState->SetScrollPositionOnly(
+        !mShared->mSaveLayoutState);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::InitLayoutHistoryState(nsILayoutHistoryState** aState) {
+  if (!mShared->mLayoutHistoryState) {
+    nsCOMPtr<nsILayoutHistoryState> historyState;
+    historyState = NS_NewLayoutHistoryState();
+    SetLayoutHistoryState(historyState);
+  }
+
+  nsCOMPtr<nsILayoutHistoryState> state = GetLayoutHistoryState();
+  state.forget(aState);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetLoadType(uint32_t* aResult) {
+  *aResult = mLoadType;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetLoadType(uint32_t aLoadType) {
+  mLoadType = aLoadType;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetID(uint32_t* aResult) {
+  *aResult = mID;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetID(uint32_t aID) {
+  mID = aID;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetIsSubFrame(bool* aFlag) {
+  *aFlag = mShared->mIsFrameNavigation;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetIsSubFrame(bool aFlag) {
+  mShared->mIsFrameNavigation = aFlag;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetHasUserInteraction(bool* aFlag) {
+  // The back button and menulist deal with root/top-level
+  // session history entries, thus we annotate only the root entry.
+  if (!mParent) {
+    *aFlag = mHasUserInteraction;
+  } else {
+    nsCOMPtr<nsISHEntry> root = nsSHistory::GetRootSHEntry(this);
+    root->GetHasUserInteraction(aFlag);
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetHasUserInteraction(bool aFlag) {
+  // The back button and menulist deal with root/top-level
+  // session history entries, thus we annotate only the root entry.
+  if (!mParent) {
+    mHasUserInteraction = aFlag;
+  } else {
+    nsCOMPtr<nsISHEntry> root = nsSHistory::GetRootSHEntry(this);
+    root->SetHasUserInteraction(aFlag);
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetHasUserActivation(bool* aFlag) {
+  *aFlag = mHasUserActivation;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetHasUserActivation(bool aFlag) {
+  mHasUserActivation = aFlag;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetCacheKey(uint32_t* aResult) {
+  *aResult = mShared->mCacheKey;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetCacheKey(uint32_t aCacheKey) {
+  mShared->mCacheKey = aCacheKey;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetContentType(nsACString& aContentType) {
+  aContentType = mShared->mContentType;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetContentType(const nsACString& aContentType) {
+  mShared->mContentType = aContentType;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::Create(
+    nsIURI* aURI, const nsAString& aTitle, nsIInputStream* aInputStream,
+    uint32_t aCacheKey, const nsACString& aContentType,
+    nsIPrincipal* aTriggeringPrincipal, nsIPrincipal* aPrincipalToInherit,
+    nsIPrincipal* aPartitionedPrincipalToInherit,
+    nsIContentSecurityPolicy* aCsp, const nsID& aDocShellID,
+    bool aDynamicCreation, nsIURI* aOriginalURI, nsIURI* aResultPrincipalURI,
+    nsIURI* aUnstrippedURI, bool aLoadReplace, nsIReferrerInfo* aReferrerInfo,
+    const nsAString& aSrcdocData, bool aSrcdocEntry, nsIURI* aBaseURI,
+    bool aSaveLayoutState, bool aExpired, bool aUserActivation) {
+  MOZ_ASSERT(
+      aTriggeringPrincipal,
+      "need a valid triggeringPrincipal to create a session history entry");
+
+  mURI = aURI;
+  mTitle = aTitle;
+  mPostData = aInputStream;
+
+  // Set the LoadType by default to loadHistory during creation
+  mLoadType = LOAD_HISTORY;
+
+  mShared->mCacheKey = aCacheKey;
+  mShared->mContentType = aContentType;
+  mShared->mTriggeringPrincipal = aTriggeringPrincipal;
+  mShared->mPrincipalToInherit = aPrincipalToInherit;
+  mShared->mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
+  mShared->mCsp = aCsp;
+  mShared->mDocShellID = aDocShellID;
+  mShared->mDynamicallyCreated = aDynamicCreation;
+
+  // By default all entries are set false for subframe flag.
+  // nsDocShell::CloneAndReplace() which creates entries for
+  // all subframe navigations, sets the flag to true.
+  mShared->mIsFrameNavigation = false;
+
+  mHasUserInteraction = false;
+
+  mShared->mExpired = aExpired;
+
+  mIsSrcdocEntry = aSrcdocEntry;
+  mSrcdocData = aSrcdocData;
+
+  mBaseURI = aBaseURI;
+
+  mLoadedInThisProcess = true;
+
+  mOriginalURI = aOriginalURI;
+  mResultPrincipalURI = aResultPrincipalURI;
+  mUnstrippedURI = aUnstrippedURI;
+  mLoadReplace = aLoadReplace;
+  mReferrerInfo = aReferrerInfo;
+
+  mHasUserActivation = aUserActivation;
+
+  mShared->mLayoutHistoryState = nullptr;
+
+  mShared->mSaveLayoutState = aSaveLayoutState;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetParent(nsISHEntry** aResult) {
+  nsCOMPtr<nsISHEntry> parent = do_QueryReferent(mParent);
+  parent.forget(aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetParent(nsISHEntry* aParent) {
+  mParent = do_GetWeakReference(aParent);
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::SetViewerBounds(const nsIntRect& aBounds) {
+  mShared->mViewerBounds = aBounds;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::GetViewerBounds(nsIntRect& aBounds) {
+  aBounds = mShared->mViewerBounds;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetTriggeringPrincipal(nsIPrincipal** aTriggeringPrincipal) {
+  NS_IF_ADDREF(*aTriggeringPrincipal = mShared->mTriggeringPrincipal);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetTriggeringPrincipal(nsIPrincipal* aTriggeringPrincipal) {
+  mShared->mTriggeringPrincipal = aTriggeringPrincipal;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetPrincipalToInherit(nsIPrincipal** aPrincipalToInherit) {
+  NS_IF_ADDREF(*aPrincipalToInherit = mShared->mPrincipalToInherit);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetPrincipalToInherit(nsIPrincipal* aPrincipalToInherit) {
+  mShared->mPrincipalToInherit = aPrincipalToInherit;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetPartitionedPrincipalToInherit(
+    nsIPrincipal** aPartitionedPrincipalToInherit) {
+  NS_IF_ADDREF(*aPartitionedPrincipalToInherit =
+                   mShared->mPartitionedPrincipalToInherit);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetPartitionedPrincipalToInherit(
+    nsIPrincipal* aPartitionedPrincipalToInherit) {
+  mShared->mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetCsp(nsIContentSecurityPolicy** aCsp) {
+  NS_IF_ADDREF(*aCsp = mShared->mCsp);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetCsp(nsIContentSecurityPolicy* aCsp) {
+  mShared->mCsp = aCsp;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::AdoptBFCacheEntry(nsISHEntry* aEntry) {
+  nsSHEntryShared* shared = static_cast<nsSHEntry*>(aEntry)->mShared;
+  NS_ENSURE_STATE(shared);
+
+  mShared = shared;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SharesDocumentWith(nsISHEntry* aEntry, bool* aOut) {
+  NS_ENSURE_ARG_POINTER(aOut);
+
+  *aOut = mShared == static_cast<nsSHEntry*>(aEntry)->mShared;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetIsSrcdocEntry(bool* aIsSrcdocEntry) {
+  *aIsSrcdocEntry = mIsSrcdocEntry;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetSrcdocData(nsAString& aSrcdocData) {
+  aSrcdocData = mSrcdocData;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetSrcdocData(const nsAString& aSrcdocData) {
+  mSrcdocData = aSrcdocData;
+  mIsSrcdocEntry = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetBaseURI(nsIURI** aBaseURI) {
+  *aBaseURI = mBaseURI;
+  NS_IF_ADDREF(*aBaseURI);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetBaseURI(nsIURI* aBaseURI) {
+  mBaseURI = aBaseURI;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetScrollRestorationIsManual(bool* aIsManual) {
+  *aIsManual = mScrollRestorationIsManual;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetScrollRestorationIsManual(bool aIsManual) {
+  mScrollRestorationIsManual = aIsManual;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetLoadedInThisProcess(bool* aLoadedInThisProcess) {
+  *aLoadedInThisProcess = mLoadedInThisProcess;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetChildCount(int32_t* aCount) {
+  *aCount = mChildren.Count();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::AddChild(nsISHEntry* aChild, int32_t aOffset,
+                    bool aUseRemoteSubframes) {
+  if (aChild) {
+    NS_ENSURE_SUCCESS(aChild->SetParent(this), NS_ERROR_FAILURE);
+  }
+
+  if (aOffset < 0) {
+    mChildren.AppendObject(aChild);
+    return NS_OK;
+  }
+
+  //
+  // Bug 52670: Ensure children are added in order.
+  //
+  //  Later frames in the child list may load faster and get appended
+  //  before earlier frames, causing session history to be scrambled.
+  //  By growing the list here, they are added to the right position.
+  //
+  //  Assert that aOffset will not be so high as to grow us a lot.
+  //
+  NS_ASSERTION(aOffset < (mChildren.Count() + 1023), "Large frames array!\n");
+
+  bool newChildIsDyn = aChild ? aChild->IsDynamicallyAdded() : false;
+
+  // If the new child is dynamically added, try to add it to aOffset, but if
+  // there are non-dynamically added children, the child must be after those.
+  if (newChildIsDyn) {
+    int32_t lastNonDyn = aOffset - 1;
+    for (int32_t i = aOffset; i < mChildren.Count(); ++i) {
+      nsISHEntry* entry = mChildren[i];
+      if (entry) {
+        if (entry->IsDynamicallyAdded()) {
+          break;
+        } else {
+          lastNonDyn = i;
+        }
+      }
+    }
+    // InsertObjectAt allows only appending one object.
+    // If aOffset is larger than Count(), we must first manually
+    // set the capacity.
+    if (aOffset > mChildren.Count()) {
+      mChildren.SetCount(aOffset);
+    }
+    if (!mChildren.InsertObjectAt(aChild, lastNonDyn + 1)) {
+      NS_WARNING("Adding a child failed!");
+      aChild->SetParent(nullptr);
+      return NS_ERROR_FAILURE;
+    }
+  } else {
+    // If the new child isn't dynamically added, it should be set to aOffset.
+    // If there are dynamically added children before that, those must be
+    // moved to be after aOffset.
+    if (mChildren.Count() > 0) {
+      int32_t start = std::min(mChildren.Count() - 1, aOffset);
+      int32_t dynEntryIndex = -1;
+      nsISHEntry* dynEntry = nullptr;
+      for (int32_t i = start; i >= 0; --i) {
+        nsISHEntry* entry = mChildren[i];
+        if (entry) {
+          if (entry->IsDynamicallyAdded()) {
+            dynEntryIndex = i;
+            dynEntry = entry;
+          } else {
+            break;
+          }
+        }
+      }
+
+      if (dynEntry) {
+        nsCOMArray<nsISHEntry> tmp;
+        tmp.SetCount(aOffset - dynEntryIndex + 1);
+        mChildren.InsertObjectsAt(tmp, dynEntryIndex);
+        NS_ASSERTION(mChildren[aOffset + 1] == dynEntry, "Whaat?");
+      }
+    }
+
+    // Make sure there isn't anything at aOffset.
+    if (aOffset < mChildren.Count()) {
+      nsISHEntry* oldChild = mChildren[aOffset];
+      if (oldChild && oldChild != aChild) {
+        // Under Fission, this can happen when a network-created iframe starts
+        // out in-process, moves out-of-process, and then switches back. At that
+        // point, we'll create a new network-created DocShell at the same index
+        // where we already have an entry for the original network-created
+        // DocShell.
+        //
+        // This should ideally stop being an issue once the Fission-aware
+        // session history rewrite is complete.
+        NS_ASSERTION(
+            aUseRemoteSubframes,
+            "Adding a child where we already have a child? This may misbehave");
+        oldChild->SetParent(nullptr);
+      }
+    }
+
+    mChildren.ReplaceObjectAt(aChild, aOffset);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::RemoveChild(nsISHEntry* aChild) {
+  NS_ENSURE_TRUE(aChild, NS_ERROR_FAILURE);
+  bool childRemoved = false;
+  if (aChild->IsDynamicallyAdded()) {
+    childRemoved = mChildren.RemoveObject(aChild);
+  } else {
+    int32_t index = mChildren.IndexOfObject(aChild);
+    if (index >= 0) {
+      // Other alive non-dynamic child docshells still keep mChildOffset,
+      // so we don't want to change the indices here.
+      mChildren.ReplaceObjectAt(nullptr, index);
+      childRemoved = true;
+    }
+  }
+  if (childRemoved) {
+    aChild->SetParent(nullptr);
+
+    // reduce the child count, i.e. remove empty children at the end
+    for (int32_t i = mChildren.Count() - 1; i >= 0 && !mChildren[i]; --i) {
+      if (!mChildren.RemoveObjectAt(i)) {
+        break;
+      }
+    }
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetChildAt(int32_t aIndex, nsISHEntry** aResult) {
+  if (aIndex >= 0 && aIndex < mChildren.Count()) {
+    *aResult = mChildren[aIndex];
+    // yes, mChildren can have holes in it.  AddChild's offset parameter makes
+    // that possible.
+    NS_IF_ADDREF(*aResult);
+  } else {
+    *aResult = nullptr;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::GetChildSHEntryIfHasNoDynamicallyAddedChild(int32_t aChildOffset,
+                                                       nsISHEntry** aChild) {
+  *aChild = nullptr;
+
+  bool dynamicallyAddedChild = false;
+  HasDynamicallyAddedChild(&dynamicallyAddedChild);
+  if (dynamicallyAddedChild) {
+    return;
+  }
+
+  // If the user did a shift-reload on this frameset page,
+  // we don't want to load the subframes from history.
+  if (IsForceReloadType(mLoadType) || mLoadType == LOAD_REFRESH) {
+    return;
+  }
+
+  /* Before looking for the subframe's url, check
+   * the expiration status of the parent. If the parent
+   * has expired from cache, then subframes will not be
+   * loaded from history in certain situations.
+   * If the user pressed reload and the parent frame has expired
+   *  from cache, we do not want to load the child frame from history.
+   */
+  if (mShared->mExpired && (mLoadType == LOAD_RELOAD_NORMAL)) {
+    // The parent has expired. Return null.
+    *aChild = nullptr;
+    return;
+  }
+  // Get the child subframe from session history.
+  GetChildAt(aChildOffset, aChild);
+  if (*aChild) {
+    // Set the parent's Load Type on the child
+    (*aChild)->SetLoadType(mLoadType);
+  }
+}
+
+NS_IMETHODIMP
+nsSHEntry::ReplaceChild(nsISHEntry* aNewEntry) {
+  NS_ENSURE_STATE(aNewEntry);
+
+  nsID docshellID;
+  aNewEntry->GetDocshellID(docshellID);
+
+  for (int32_t i = 0; i < mChildren.Count(); ++i) {
+    if (mChildren[i]) {
+      nsID childDocshellID;
+      nsresult rv = mChildren[i]->GetDocshellID(childDocshellID);
+      NS_ENSURE_SUCCESS(rv, rv);
+      if (docshellID == childDocshellID) {
+        mChildren[i]->SetParent(nullptr);
+        mChildren.ReplaceObjectAt(aNewEntry, i);
+        return aNewEntry->SetParent(this);
+      }
+    }
+  }
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP_(void) nsSHEntry::ClearEntry() {
+  int32_t childCount = GetChildCount();
+  // Remove all children of this entry
+  for (int32_t i = childCount - 1; i >= 0; i--) {
+    nsCOMPtr<nsISHEntry> child;
+    GetChildAt(i, getter_AddRefs(child));
+    RemoveChild(child);
+  }
+  AbandonBFCacheEntry();
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetStateData(nsIStructuredCloneContainer** aContainer) {
+  NS_IF_ADDREF(*aContainer = mStateData);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetStateData(nsIStructuredCloneContainer* aContainer) {
+  mStateData = aContainer;
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(bool)
+nsSHEntry::IsDynamicallyAdded() { return mShared->mDynamicallyCreated; }
+
+NS_IMETHODIMP
+nsSHEntry::HasDynamicallyAddedChild(bool* aAdded) {
+  *aAdded = false;
+  for (int32_t i = 0; i < mChildren.Count(); ++i) {
+    nsISHEntry* entry = mChildren[i];
+    if (entry) {
+      *aAdded = entry->IsDynamicallyAdded();
+      if (*aAdded) {
+        break;
+      }
+    }
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetDocshellID(nsID& aID) {
+  aID = mShared->mDocShellID;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetDocshellID(const nsID& aID) {
+  mShared->mDocShellID = aID;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetLastTouched(uint32_t* aLastTouched) {
+  *aLastTouched = mShared->mLastTouched;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetLastTouched(uint32_t aLastTouched) {
+  mShared->mLastTouched = aLastTouched;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetShistory(nsISHistory** aSHistory) {
+  nsCOMPtr<nsISHistory> shistory(do_QueryReferent(mShared->mSHistory));
+  shistory.forget(aSHistory);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetShistory(nsISHistory* aSHistory) {
+  nsWeakPtr shistory = do_GetWeakReference(aSHistory);
+  // mSHistory can not be changed once it's set
+  MOZ_ASSERT(!mShared->mSHistory || (mShared->mSHistory == shistory));
+  mShared->mSHistory = shistory;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetLoadTypeAsHistory() {
+  // Set the LoadType by default to loadHistory during creation
+  mLoadType = LOAD_HISTORY;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetPersist(bool* aPersist) {
+  *aPersist = mPersist;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetPersist(bool aPersist) {
+  mPersist = aPersist;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::CreateLoadInfo(nsDocShellLoadState** aLoadState) {
+  nsCOMPtr<nsIURI> uri = GetURI();
+  RefPtr<nsDocShellLoadState> loadState(new nsDocShellLoadState(uri));
+
+  nsCOMPtr<nsIURI> originalURI = GetOriginalURI();
+  loadState->SetOriginalURI(originalURI);
+
+  mozilla::Maybe<nsCOMPtr<nsIURI>> emplacedResultPrincipalURI;
+  nsCOMPtr<nsIURI> resultPrincipalURI = GetResultPrincipalURI();
+  emplacedResultPrincipalURI.emplace(std::move(resultPrincipalURI));
+  loadState->SetMaybeResultPrincipalURI(emplacedResultPrincipalURI);
+
+  nsCOMPtr<nsIURI> unstrippedURI = GetUnstrippedURI();
+  loadState->SetUnstrippedURI(unstrippedURI);
+
+  loadState->SetLoadReplace(GetLoadReplace());
+  nsCOMPtr<nsIInputStream> postData = GetPostData();
+  loadState->SetPostDataStream(postData);
+
+  nsAutoCString contentType;
+  GetContentType(contentType);
+  loadState->SetTypeHint(contentType);
+
+  nsCOMPtr<nsIPrincipal> triggeringPrincipal = GetTriggeringPrincipal();
+  loadState->SetTriggeringPrincipal(triggeringPrincipal);
+  nsCOMPtr<nsIPrincipal> principalToInherit = GetPrincipalToInherit();
+  loadState->SetPrincipalToInherit(principalToInherit);
+  nsCOMPtr<nsIPrincipal> partitionedPrincipalToInherit =
+      GetPartitionedPrincipalToInherit();
+  loadState->SetPartitionedPrincipalToInherit(partitionedPrincipalToInherit);
+  nsCOMPtr<nsIContentSecurityPolicy> csp = GetCsp();
+  loadState->SetCsp(csp);
+  nsCOMPtr<nsIReferrerInfo> referrerInfo = GetReferrerInfo();
+  loadState->SetReferrerInfo(referrerInfo);
+
+  // Do not inherit principal from document (security-critical!);
+  uint32_t flags = nsDocShell::InternalLoad::INTERNAL_LOAD_FLAGS_NONE;
+
+  // Passing nullptr as aSourceDocShell gives the same behaviour as before
+  // aSourceDocShell was introduced. According to spec we should be passing
+  // the source browsing context that was used when the history entry was
+  // first created. bug 947716 has been created to address this issue.
+  nsAutoString srcdoc;
+  nsCOMPtr<nsIURI> baseURI;
+  if (GetIsSrcdocEntry()) {
+    GetSrcdocData(srcdoc);
+    baseURI = GetBaseURI();
+    flags |= nsDocShell::InternalLoad::INTERNAL_LOAD_FLAGS_IS_SRCDOC;
+  } else {
+    srcdoc = VoidString();
+  }
+  loadState->SetSrcdocData(srcdoc);
+  loadState->SetBaseURI(baseURI);
+  loadState->SetInternalLoadFlags(flags);
+
+  loadState->SetFirstParty(true);
+
+  loadState->SetHasValidUserGestureActivation(GetHasUserActivation());
+
+  loadState->SetSHEntry(this);
+
+  // When we create a load state from the history entry we already know if
+  // https-first was able to upgrade the request from http to https. There is no
+  // point in re-retrying to upgrade.
+  loadState->SetIsExemptFromHTTPSOnlyMode(true);
+
+  loadState.forget(aLoadState);
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::SyncTreesForSubframeNavigation(
+    nsISHEntry* aEntry, mozilla::dom::BrowsingContext* aTopBC,
+    mozilla::dom::BrowsingContext* aIgnoreBC) {
+  // XXX Keep this in sync with
+  // SessionHistoryEntry::SyncTreesForSubframeNavigation
+  //
+  // We need to sync up the browsing context and session history trees for
+  // subframe navigation.  If the load was in a subframe, we forward up to
+  // the top browsing context, which will then recursively sync up all browsing
+  // contexts to their corresponding entries in the new session history tree. If
+  // we don't do this, then we can cache a content viewer on the wrong cloned
+  // entry, and subsequently restore it at the wrong time.
+  nsCOMPtr<nsISHEntry> newRootEntry = nsSHistory::GetRootSHEntry(aEntry);
+  if (newRootEntry) {
+    // newRootEntry is now the new root entry.
+    // Find the old root entry as well.
+
+    // Need a strong ref. on |oldRootEntry| so it isn't destroyed when
+    // SetChildHistoryEntry() does SwapHistoryEntries() (bug 304639).
+    nsCOMPtr<nsISHEntry> oldRootEntry = nsSHistory::GetRootSHEntry(this);
+
+    if (oldRootEntry) {
+      nsSHistory::SwapEntriesData data = {aIgnoreBC, newRootEntry, nullptr};
+      nsSHistory::SetChildHistoryEntry(oldRootEntry, aTopBC, 0, &data);
+    }
+  }
+}
+
+void nsSHEntry::EvictContentViewer() {
+  nsCOMPtr<nsIContentViewer> viewer = GetContentViewer();
+  if (viewer) {
+    mShared->NotifyListenersContentViewerEvicted();
+    // Drop the presentation state before destroying the viewer, so that
+    // document teardown is able to correctly persist the state.
+    SetContentViewer(nullptr);
+    SyncPresentationState();
+    viewer->Destroy();
+  }
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetContentViewer(nsIContentViewer* aViewer) {
+  return GetState()->SetContentViewer(aViewer);
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetContentViewer(nsIContentViewer** aResult) {
+  *aResult = GetState()->mContentViewer;
+  NS_IF_ADDREF(*aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetIsInBFCache(bool* aResult) {
+  *aResult = !!GetState()->mContentViewer;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::Clone(nsISHEntry** aResult) {
+  nsCOMPtr<nsISHEntry> entry = new nsSHEntry(*this);
+  entry.forget(aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetSaveLayoutStateFlag(bool* aFlag) {
+  *aFlag = mShared->mSaveLayoutState;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetSaveLayoutStateFlag(bool aFlag) {
+  mShared->mSaveLayoutState = aFlag;
+  if (mShared->mLayoutHistoryState) {
+    mShared->mLayoutHistoryState->SetScrollPositionOnly(!aFlag);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetWindowState(nsISupports* aState) {
+  GetState()->mWindowState = aState;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetWindowState(nsISupports** aState) {
+  NS_IF_ADDREF(*aState = GetState()->mWindowState);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetRefreshURIList(nsIMutableArray** aList) {
+  NS_IF_ADDREF(*aList = GetState()->mRefreshURIList);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetRefreshURIList(nsIMutableArray* aList) {
+  GetState()->mRefreshURIList = aList;
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::AddChildShell(nsIDocShellTreeItem* aShell) {
+  MOZ_ASSERT(aShell, "Null child shell added to history entry");
+  GetState()->mChildShells.AppendObject(aShell);
+}
+
+NS_IMETHODIMP
+nsSHEntry::ChildShellAt(int32_t aIndex, nsIDocShellTreeItem** aShell) {
+  NS_IF_ADDREF(*aShell = GetState()->mChildShells.SafeObjectAt(aIndex));
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsSHEntry::ClearChildShells() { GetState()->mChildShells.Clear(); }
+
+NS_IMETHODIMP_(void)
+nsSHEntry::SyncPresentationState() { GetState()->SyncPresentationState(); }
+
+nsDocShellEditorData* nsSHEntry::ForgetEditorData() {
+  // XXX jlebar Check how this is used.
+  return GetState()->mEditorData.release();
+}
+
+void nsSHEntry::SetEditorData(nsDocShellEditorData* aData) {
+  NS_ASSERTION(!(aData && GetState()->mEditorData),
+               "We're going to overwrite an owning ref!");
+  if (GetState()->mEditorData != aData) {
+    GetState()->mEditorData = mozilla::WrapUnique(aData);
+  }
+}
+
+bool nsSHEntry::HasDetachedEditor() {
+  return GetState()->mEditorData != nullptr;
+}
+
+bool nsSHEntry::HasBFCacheEntry(
+    mozilla::dom::SHEntrySharedParentState* aEntry) {
+  return GetState() == aEntry;
+}
+
+NS_IMETHODIMP
+nsSHEntry::AbandonBFCacheEntry() {
+  mShared = GetState()->Duplicate();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetBfcacheID(uint64_t* aBFCacheID) {
+  *aBFCacheID = mShared->GetId();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::GetWireframe(JSContext* aCx, JS::MutableHandle<JS::Value> aOut) {
+  aOut.set(JS::NullValue());
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSHEntry::SetWireframe(JSContext* aCx, JS::Handle<JS::Value> aArg) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}