Safeguard for webMediaPlayer() access

Source/modules/imagebitmap/ImageBitmapFactories.cpp

 /*
  * Copyright (c) 2013, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 106 matching lines @@
 {
     IntSize s = sizeFor(video);
     return createImageBitmap(scriptState, eventTarget, video, 0, 0, s.width(), s.height(), exceptionState);
 }
 
 ScriptPromise ImageBitmapFactories::createImageBitmap(ScriptState* scriptState, EventTarget& eventTarget, HTMLVideoElement* video, int sx, int sy, int sw, int sh, ExceptionState& exceptionState)
 {
     // This variant does not work in worker threads.
     ASSERT(eventTarget.toDOMWindow());
 
+    if (!video->webMediaPlayer()) {
+        exceptionState.throwDOMException(InvalidStateError, "No player can be retrieved from the provided video element.");
+        return ScriptPromise();
+    }
     if (video->networkState() == HTMLMediaElement::NETWORK_EMPTY) {
         exceptionState.throwDOMException(InvalidStateError, "The provided element has not retrieved data.");
         return ScriptPromise();
     }
     if (video->readyState() <= HTMLMediaElement::HAVE_METADATA) {

[acolwell GONE FROM CHROMIUM, 2014/06/09 23:09:36]

nit: I think you should probably just make the null check here and add a FIXME
comment saying that the null check should be removed once we fix Bug 382721.

[Srirama, 2014/06/10 05:50:25]

Done.

         exceptionState.throwDOMException(InvalidStateError, "The provided element's player has no current data.");
         return ScriptPromise();
     }
     if (!sw || !sh) {
         exceptionState.throwDOMException(IndexSizeError, String::format("The source %s provided is 0.", sw ? "height" : "width"));
         return ScriptPromise();
     }
     if (!video->hasSingleSecurityOrigin()) {
         exceptionState.throwSecurityError("The source video contains image data from multiple origins.");
         return ScriptPromise();
@@ skipping 189 matching lines @@
 {
     rejectPromise();
 }
 
 void ImageBitmapFactories::ImageBitmapLoader::trace(Visitor* visitor)
 {
     visitor->trace(m_factory);
 }
 
 } // namespace WebCore