Bug 405951. Thunderbird: newsgroup/feed messages blank in virtual buffer, r=surkov, a=blocking1.9

accessible/src/base/nsCaretAccessible.cpp

@@ -132,13 +132,12 @@ nsresult nsCaretAccessible::SetControlSelectionListener(nsIDOMNode *aCurrentNode
   return selPrivate->AddSelectionListener(this);
 }
 
-nsresult nsCaretAccessible::AddDocSelectionListener(nsIDOMDocument *aDoc)
+nsresult
+nsCaretAccessible::AddDocSelectionListener(nsIPresShell *aShell)
 {
   NS_ENSURE_TRUE(mRootAccessible, NS_ERROR_FAILURE);
 
-  nsCOMPtr<nsIDocument> doc = do_QueryInterface(aDoc);
-  NS_ENSURE_TRUE(doc, NS_ERROR_FAILURE);
-  nsCOMPtr<nsISelectionController> selCon = do_QueryInterface(doc->GetPrimaryShell());
+  nsCOMPtr<nsISelectionController> selCon = do_QueryInterface(aShell);
   NS_ENSURE_TRUE(selCon, NS_ERROR_FAILURE);
 
   nsCOMPtr<nsISelection> domSel;
@@ -149,12 +148,10 @@ nsresult nsCaretAccessible::AddDocSelectionListener(nsIDOMDocument *aDoc)
   return selPrivate->AddSelectionListener(this);
 }
 
-nsresult nsCaretAccessible::RemoveDocSelectionListener(nsIDOMDocument *aDoc)
+nsresult
+nsCaretAccessible::RemoveDocSelectionListener(nsIPresShell *aShell)
 {
-  nsCOMPtr<nsIDocument> doc = do_QueryInterface(aDoc);
-  NS_ENSURE_TRUE(doc, NS_ERROR_FAILURE);
-
-  nsCOMPtr<nsISelectionController> selCon = do_QueryInterface(doc->GetPrimaryShell());
+  nsCOMPtr<nsISelectionController> selCon = do_QueryInterface(aShell);
   NS_ENSURE_TRUE(selCon, NS_ERROR_FAILURE);
 
   nsCOMPtr<nsISelection> domSel;

accessible/src/base/nsCaretAccessible.h

@@ -103,17 +103,19 @@ public:
    * Start listening to selection events for a given document
    * More than one document's selection events can be listened to
    * at the same time, by a given nsCaretAccessible
-   * @param aDocument   Document to listen to selection events for.
+   * @param aShell   PresShell for document to listen to selection events from.
    */
-  nsresult AddDocSelectionListener(nsIDOMDocument *aDoc);
+  nsresult AddDocSelectionListener(nsIPresShell *aShell);
 
   /**
    * Stop listening to selection events for a given document
    * If the document goes away, this method needs to be called for 
-   * that document by the owner of the caret
-   * @param aDocument   Document to listen to selection events for.
+   * that document by the owner of the caret. We use presShell because
+   * instead of document because it is more direct than getting it from
+   * the document, and in any case it is unavailable from the doc after a pagehide.
+   * @param aShell   PresShell for document to no longer listen to selection events from.
    */
-  nsresult RemoveDocSelectionListener(nsIDOMDocument *aDoc);
+  nsresult RemoveDocSelectionListener(nsIPresShell *aShell);
 
   nsRect GetCaretRect(nsIWidget **aOutWidget);
 

accessible/src/base/nsDocAccessible.cpp

@@ -669,8 +669,7 @@ nsresult nsDocAccessible::AddEventListeners()
     NS_ENSURE_TRUE(rootAccessible, NS_ERROR_FAILURE);
     nsRefPtr<nsCaretAccessible> caretAccessible = rootAccessible->GetCaretAccessible();
     if (caretAccessible) {
-      nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(mDocument);
-      caretAccessible->AddDocSelectionListener(domDoc);
+      caretAccessible->AddDocSelectionListener(presShell);
     }
   }
 
@@ -698,8 +697,8 @@ nsresult nsDocAccessible::RemoveEventListeners()
   if (rootAccessible) {
     nsRefPtr<nsCaretAccessible> caretAccessible = rootAccessible->GetCaretAccessible();
     if (caretAccessible) {
-      nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(mDocument);
-      caretAccessible->RemoveDocSelectionListener(domDoc);
+      nsCOMPtr<nsIPresShell> presShell(GetPresShell());
+      caretAccessible->RemoveDocSelectionListener(presShell);
     }
   }