Bug 815671 part 3. Make nsXULPopupManager::GetVisiblePopups use an array out param instead of returning array object copies. r=roc

dom/base/nsFocusManager.cpp

@@ -3111,7 +3111,8 @@ nsFocusManager::GetNextTabbablePanel(nsIDocument* aDocument, nsIFrame* aCurrentP
     return nullptr;
 
   // Iterate through the array backwards if aForward is false.
-  nsTArray<nsIFrame *> popups = pm->GetVisiblePopups();
+  nsTArray<nsIFrame *> popups;
+  pm->GetVisiblePopups(popups);
   int32_t i = aForward ? 0 : popups.Length() - 1;
   int32_t end = aForward ? popups.Length() : -1;
 

layout/base/nsCaret.cpp

@@ -934,7 +934,8 @@ bool nsCaret::IsMenuPopupHidingCaret()
 #ifdef MOZ_XUL
   // Check if there are open popups.
   nsXULPopupManager *popMgr = nsXULPopupManager::GetInstance();
-  nsTArray<nsIFrame*> popups = popMgr->GetVisiblePopups();
+  nsTArray<nsIFrame*> popups;
+  popMgr->GetVisiblePopups(popups);
 
   if (popups.Length() == 0)
     return false; // No popups, so caret can't be hidden by them.

layout/base/nsLayoutUtils.cpp

@@ -1192,7 +1192,8 @@ nsLayoutUtils::GetPopupFrameForEventCoordinates(nsPresContext* aPresContext,
   if (!pm) {
     return nullptr;
   }
-  nsTArray<nsIFrame*> popups = pm->GetVisiblePopups();
+  nsTArray<nsIFrame*> popups;
+  pm->GetVisiblePopups(popups);
   uint32_t i;
   // Search from top to bottom
   for (i = 0; i < popups.Length(); i++) {

layout/xul/base/public/nsXULPopupManager.h

@@ -490,7 +490,7 @@ public:
    * Return an array of all the open and visible popup frames for
    * menus, in order from top to bottom.
    */
-  nsTArray<nsIFrame *> GetVisiblePopups();
+  void GetVisiblePopups(nsTArray<nsIFrame *>& aPopups);
 
   /**
    * Get the node that last triggered a popup or tooltip in the document

layout/xul/base/src/nsXULPopupManager.cpp

@@ -1325,15 +1325,15 @@ nsXULPopupManager::GetTopPopup(nsPopupType aType)
   return nullptr;
 }
 
-nsTArray<nsIFrame *>
-nsXULPopupManager::GetVisiblePopups()
+void
+nsXULPopupManager::GetVisiblePopups(nsTArray<nsIFrame *>& aPopups)
 {
-  nsTArray<nsIFrame *> popups;
+  aPopups.Clear();
 
   nsMenuChainItem* item = mPopups;
   while (item) {
     if (item->Frame()->PopupState() == ePopupOpenAndVisible)
-      popups.AppendElement(static_cast<nsIFrame*>(item->Frame()));
+      aPopups.AppendElement(static_cast<nsIFrame*>(item->Frame()));
     item = item->GetParent();
   }
 
@@ -1342,12 +1342,10 @@ nsXULPopupManager::GetVisiblePopups()
     // skip panels which are not open and visible as well as draggable popups,
     // as those don't respond to events.
     if (item->Frame()->PopupState() == ePopupOpenAndVisible && !item->Frame()->IsDragPopup()) {
-      popups.AppendElement(static_cast<nsIFrame*>(item->Frame()));
+      aPopups.AppendElement(static_cast<nsIFrame*>(item->Frame()));
     }
     item = item->GetParent();
   }
-
-  return popups;
 }
 
 already_AddRefed<nsIDOMNode>