From 2f9adce2c3f483077d454d722d0abb9294cf6a03 Mon Sep 17 00:00:00 2001
From: Markus Stange <mstange@themasta.com>
Date: Mon, 5 May 2014 10:23:18 +0200
Subject: [PATCH] Bug 1000875 - Give
 nsDOMWindowUtils::CheckAndClearPaintedState the ability to check paints of
 canvas frames. r=roc

---
 dom/base/nsDOMWindowUtils.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/dom/base/nsDOMWindowUtils.cpp b/dom/base/nsDOMWindowUtils.cpp
index 3762d5a5ecb..0f03158710a 100644
--- a/dom/base/nsDOMWindowUtils.cpp
+++ b/dom/base/nsDOMWindowUtils.cpp
@@ -3076,6 +3076,17 @@ nsDOMWindowUtils::CheckAndClearPaintedState(nsIDOMElement* aElement, bool* aResu
     return NS_OK;
   }
 
+  // Get the outermost frame for the content node, so that we can test
+  // canvasframe invalidations by observing the documentElement.
+  for (;;) {
+    nsIFrame* parentFrame = frame->GetParent();
+    if (parentFrame && parentFrame->GetContent() == content) {
+      frame = parentFrame;
+    } else {
+      break;
+    }
+  }
+
   *aResult = frame->CheckAndClearPaintedState();
   return NS_OK;
 }