Bug 476948: Need to be able to clear outstanding MozAfterPaint events r+sr=roc

dom/public/idl/base/nsIDOMWindowUtils.idl

@@ -307,6 +307,8 @@ interface nsIDOMWindowUtils : nsISupports {
    */
   void suppressEventHandling(in boolean aSuppress);
 
+  void clearMozAfterPaintEvents();
+
   /**
    * Disable or enable non synthetic test mouse events on *all* windows.
    *

dom/src/base/nsDOMWindowUtils.cpp

@@ -683,6 +683,16 @@ nsDOMWindowUtils::GetIsMozAfterPaintPending(PRBool *aResult)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsDOMWindowUtils::ClearMozAfterPaintEvents()
+{
+  nsPresContext* presContext = GetPresContext();
+  if (!presContext)
+    return NS_OK;
+  presContext->ClearMozAfterPaintEvents();
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsDOMWindowUtils::DisableNonTestMouseEvents(PRBool aDisable)
 {

layout/base/nsPresContext.h

@@ -802,6 +802,11 @@ public:
     return !mSameDocDirtyRegion.IsEmpty() || !mCrossDocDirtyRegion.IsEmpty();
   }
 
+  void ClearMozAfterPaintEvents() {
+    mSameDocDirtyRegion.SetEmpty();
+    mCrossDocDirtyRegion.SetEmpty();
+  }
+
 protected:
   friend class nsRunnableMethod<nsPresContext>;
   NS_HIDDEN_(void) ThemeChangedInternal();