From aa90d7dcb63e7833a7e4406f5389fc3880bb2ace Mon Sep 17 00:00:00 2001
From: Bill McCloskey <billm@mozilla.com>
Date: Fri, 6 Jan 2017 13:57:26 -0800
Subject: [PATCH] Bug 1328423 - Add AutoAssertNoContentJS to PresShell::Paint
 (r=dvander)

MozReview-Commit-ID: 4M4pYZSygPH
---
 layout/base/PresShell.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/layout/base/PresShell.cpp b/layout/base/PresShell.cpp
index 297b5ee3baada..469708440e8ca 100644
--- a/layout/base/PresShell.cpp
+++ b/layout/base/PresShell.cpp
@@ -168,6 +168,7 @@
 #include "LayerTreeInvalidation.h"
 #include "mozilla/css/ImageLoader.h"
 #include "mozilla/dom/DocumentTimeline.h"
+#include "mozilla/dom/ScriptSettings.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Telemetry.h"
 #include "nsCanvasFrame.h"
@@ -6239,6 +6240,13 @@ PresShell::Paint(nsView*        aViewToPaint,
   PROFILER_LABEL("PresShell", "Paint",
     js::ProfileEntry::Category::GRAPHICS);
 
+  Maybe<js::AutoAssertNoContentJS> nojs;
+  if (!(aFlags & nsIPresShell::PAINT_COMPOSITE)) {
+    // We need to allow content JS when the flag is set since we may trigger
+    // MozAfterPaint events in content in those cases.
+    nojs.emplace(dom::danger::GetJSContext());
+  }
+
   NS_ASSERTION(!mIsDestroying, "painting a destroyed PresShell");
   NS_ASSERTION(aViewToPaint, "null view");