Bug 394887, create widgets for popups lazily, second attempt with a slight change to see if performance is ok

layout/xul/base/src/nsMenuPopupFrame.cpp

@@ -254,6 +254,28 @@ nsMenuPopupFrame::SetInitialChildList(nsIAtom* aListName,
   return nsBoxFrame::SetInitialChildList(aListName, aChildList);
 }
 
+PRBool
+nsMenuPopupFrame::IsLeaf() const
+{
+  if (mGeneratedChildren)
+    return PR_FALSE;
+
+  if (mPopupType != ePopupTypeMenu) {
+    // any panel with a type attribute, such as the autocomplete popup,
+    // is always generated right away.
+    return !mContent->HasAttr(kNameSpaceID_None, nsGkAtoms::type);
+  }
+
+  // menu popups generate their child frames lazily only when opened, so
+  // behave like a leaf frame. However, generate child frames normally if
+  // the parent menu has a sizetopopup attribute. In this case the size of
+  // the parent menu is dependant on the size of the popup, so the frames
+  // need to exist in order to calculate this size.
+  nsIContent* parentContent = mContent->GetParent();
+  return (parentContent &&
+          !parentContent->HasAttr(kNameSpaceID_None, nsGkAtoms::sizetopopup));
+}
+
 void
 nsMenuPopupFrame::AdjustView()
 {

layout/xul/base/src/nsMenuPopupFrame.h

@@ -183,22 +183,7 @@ public:
   NS_IMETHOD SetInitialChildList(nsIAtom*        aListName,
                                  nsIFrame*       aChildList);
 
-  virtual PRBool IsLeaf() const
-  {
-    if (!mGeneratedChildren && mPopupType == ePopupTypeMenu) {
-      // menu popups generate their child frames lazily only when opened, so
-      // behave like a leaf frame. However, generate child frames normally if
-      // the parent menu has a sizetopopup attribute. In this case the size of
-      // the parent menu is dependant on the size of the popup, so the frames
-      // need to exist in order to calculate this size.
-      nsIContent* parentContent = mContent->GetParent();
-      if (parentContent &&
-          !parentContent->HasAttr(kNameSpaceID_None, nsGkAtoms::sizetopopup))
-        return PR_TRUE;
-    }
-
-    return PR_FALSE;
-  }
+  virtual PRBool IsLeaf() const;
 
   // AdjustView should be called by the parent frame after the popup has been
   // laid out, so that the view can be shown.