Remove some null checks in MediaValuesCached that are now redundant.

Source/core/css/MediaValuesCached.cpp

Index: Source/core/css/MediaValuesCached.cpp
diff --git a/Source/core/css/MediaValuesCached.cpp b/Source/core/css/MediaValuesCached.cpp
index 8f0816a52bf22e4d83a0d64e88a6324a5d014f78..0e0b65797bbe3259f1a4c41a0413ccff28e71576 100644
--- a/Source/core/css/MediaValuesCached.cpp
+++ b/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));
 }