From 22f63d0a84cb13bbb7165b3373257a17edc612c3 Mon Sep 17 00:00:00 2001
From: "bryner%brianryner.com"
 <bryner%brianryner.com@18797224-902f-48f8-a5cc-f745e15eee43>
Date: Mon, 26 Jun 2006 18:48:52 +0000
Subject: [PATCH] Clear the old child docshells when SetDOMDocument is called,
 so that they don't get persisted in session history before they're GC'd. 
 Also, update SHEntry to hold strong references to the child docshells.  Bug
 319551, r=sicking sr=bzbarsky

git-svn-id: svn://10.0.0.236/trunk@200898 18797224-902f-48f8-a5cc-f745e15eee43
---
 mozilla/docshell/shistory/public/nsISHEntry.idl |  4 +---
 mozilla/docshell/shistory/src/nsSHEntry.cpp     |  6 ++----
 mozilla/docshell/shistory/src/nsSHEntry.h       |  2 +-
 mozilla/layout/base/nsDocumentViewer.cpp        | 13 +++++++++++++
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/mozilla/docshell/shistory/public/nsISHEntry.idl b/mozilla/docshell/shistory/public/nsISHEntry.idl
index 39c88dfa5ac..dcc4efb6344 100644
--- a/mozilla/docshell/shistory/public/nsISHEntry.idl
+++ b/mozilla/docshell/shistory/public/nsISHEntry.idl
@@ -82,9 +82,7 @@ interface nsISHEntry : nsIHistoryEntry
     [noscript] void setViewerBounds([const] in nsRect bounds);
 
     /**
-     * Saved child docshells corresponding to contentViewer.  There are weak
-     * references since it's assumed that the content viewer's document has
-     * an owning reference to the subdocument for each shell.  The child shells
+     * Saved child docshells corresponding to contentViewer.  The child shells
      * are restored as children of the parent docshell, in this order, when the
      * parent docshell restores a saved presentation.
      */
diff --git a/mozilla/docshell/shistory/src/nsSHEntry.cpp b/mozilla/docshell/shistory/src/nsSHEntry.cpp
index b4f33592ddc..947bcfd8f90 100644
--- a/mozilla/docshell/shistory/src/nsSHEntry.cpp
+++ b/mozilla/docshell/shistory/src/nsSHEntry.cpp
@@ -572,16 +572,14 @@ NS_IMETHODIMP
 nsSHEntry::AddChildShell(nsIDocShellTreeItem *aShell)
 {
   NS_ASSERTION(aShell, "Null child shell added to history entry");
-  mChildShells.AppendElement(aShell);
+  mChildShells.AppendObject(aShell);
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsSHEntry::ChildShellAt(PRInt32 aIndex, nsIDocShellTreeItem **aShell)
 {
-  NS_IF_ADDREF(*aShell =
-               NS_STATIC_CAST(nsIDocShellTreeItem*,
-                              mChildShells.SafeElementAt(aIndex)));
+  NS_IF_ADDREF(*aShell = mChildShells.SafeObjectAt(aIndex));
   return NS_OK;
 }
 
diff --git a/mozilla/docshell/shistory/src/nsSHEntry.h b/mozilla/docshell/shistory/src/nsSHEntry.h
index 0a3a0b6c959..ba16e97a7bc 100644
--- a/mozilla/docshell/shistory/src/nsSHEntry.h
+++ b/mozilla/docshell/shistory/src/nsSHEntry.h
@@ -102,7 +102,7 @@ private:
   nsISHEntry *                    mParent;  // weak reference
   nsCOMPtr<nsISupports>           mWindowState;
   nsRect                          mViewerBounds;
-  nsVoidArray                     mChildShells;
+  nsCOMArray<nsIDocShellTreeItem> mChildShells;
   nsCOMPtr<nsISupportsArray>      mRefreshURIList;
   nsCOMPtr<nsISupports>           mOwner;
 };
diff --git a/mozilla/layout/base/nsDocumentViewer.cpp b/mozilla/layout/base/nsDocumentViewer.cpp
index a4f17d0ab92..39a053f2510 100644
--- a/mozilla/layout/base/nsDocumentViewer.cpp
+++ b/mozilla/layout/base/nsDocumentViewer.cpp
@@ -1476,6 +1476,19 @@ DocumentViewerImpl::Destroy()
     if (mPrintEngine->CheckBeforeDestroy()) {
       return NS_OK;
     }
+
+    // Clear the list of old child docshells. CChild docshells for the new
+    // document will be constructed as frames are created.
+    nsCOMPtr<nsIDocShellTreeNode> node = do_QueryInterface(container);
+    if (node) {
+      PRInt32 count;
+      node->GetChildCount(&count);
+      for (PRInt32 i = 0; i < count; ++i) {
+        nsCOMPtr<nsIDocShellTreeItem> child;
+        node->GetChildAt(0, getter_AddRefs(child));
+        node->RemoveChild(child);
+      }
+    }
   }
 #endif