Remove some null checks in MediaValuesCached that are now redundant.

Scripting is forbidden during Document::detach() now, so these checks
are no longer needed.

BUG=367210,371084

Review URL: https://codereview.chromium.org/710153002

git-svn-id: svn://svn.chromium.org/blink/trunk@185061 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/css/MediaValuesCached.cpp

@@ -31,9 +31,9 @@ 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());
-    // FIXME - Because of crbug.com/371084, document()->renderView() may be null here.
-    if (!frame || !frame->view() || !frame->document() || !frame->document()->renderView())
+    if (!frame || !frame->view())
         return adoptRef(new MediaValuesCached());
+    ASSERT(frame->document() && frame->document()->renderView());
     return adoptRef(new MediaValuesCached(frame));
 }