A speculative fix for a MediaValues related crash

Source/core/css/MediaValuesCached.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/css/MediaValuesCached.h"
 
 #include "core/css/CSSPrimitiveValue.h"
 #include "core/dom/Document.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 16 matching lines @@
 {
     Document* executingDocument = document.importsController() ? document.importsController()->master() : &document;
     ASSERT(executingDocument);
     return MediaValuesCached::create(executingDocument->frame());
 }
 
 PassRefPtr<MediaValues> MediaValuesCached::create(LocalFrame* frame)
 {
     // FIXME - Added an assert here so we can better understand when a frame is present without its view().
     ASSERT(!frame || frame->view());
-    if (!frame || !frame->view())
+    // FIXME - Because of crbug.com/371084, document()->renderView() may be null here.
+    if (!frame || !frame->view() || !frame->document() || !frame->document()->renderView())
         return adoptRef(new MediaValuesCached());
     return adoptRef(new MediaValuesCached(frame));
 }
 
 MediaValuesCached::MediaValuesCached()
 {
 }
 
 MediaValuesCached::MediaValuesCached(LocalFrame* frame)
 {
@@ skipping 111 matching lines @@
 {
     return 0;
 }
 
 bool MediaValuesCached::hasValues() const
 {
     return true;
 }
 
 } // namespace