Delay resetting image animation, if possible.

third_party/WebKit/Source/core/fetch/ImageResource.cpp

Index: third_party/WebKit/Source/core/fetch/ImageResource.cpp
diff --git a/third_party/WebKit/Source/core/fetch/ImageResource.cpp b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
index 9d49d113f60ecde90d37167e3f1fdeadbb0c09a3..516fed78f528dadcb49927b73ec2c0e43fcd3ecb 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
@@ -204,10 +204,23 @@ void ImageResource::destroyDecodedDataIfPossible()
     }
 }
 
-void ImageResource::allClientsAndObserversRemoved()
+void ImageResource::doResetAnimation()
 {
-    if (m_image && !errorOccurred())
+    if (m_image)
         m_image->resetAnimation();
+}
+
+void ImageResource::allClientsAndObserversRemoved()
+{
+    if (m_image && !errorOccurred()) {
+        // If possible, delay the resetting until back at the event loop.
+        // Doing so after a conservative GC prevents resetAnimation() from
+        // upsetting ongoing animation updates (crbug.com/613709)
+        if (!ThreadHeap::willObjectBeLazilySwept(this))
+            Platform::current()->currentThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&ImageResource::doResetAnimation, WeakPersistentThisPointer<ImageResource>(this)));
+        else
+            m_image->resetAnimation();
+    }
     if (m_multipartParser)
         m_multipartParser->cancel();
     Resource::allClientsAndObserversRemoved();