Ship image-rendering: pixelated to stable.

This also adds the value to DevTools.

Intent to Ship:
https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/zSasd2LL8Mc

BUG=317991,106662,260739,134040

Review URL: https://codereview.chromium.org/396063007

git-svn-id: svn://svn.chromium.org/blink/trunk@178653 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Oilpan: WebAudio: Reduce RefPtr and raw pointers to AudioNode.

- Replace Vector<PannerNode*> in AudioListener with
  WillBeHeapVector<RawPtrWillBeMember<PannerNode>>.

- Replace RefPtr<MediaElementAudioSourceNode> in MediaElementAudioSourceNode
  with RefPtrWillBePersistent<MediaElementAudioSourceNode>.

- Replace RefPtr<OfflineAudioDestinationNode> in OfflineAudioDestinationNode
  with RefPtrWillBePersistent<OfflineAudioDestinationNode>

These pointers are not connection-references. We can safely replace
them to Oilpan types.

BUG=395940,395941

Review URL: https://codereview.chromium.org/407053004

git-svn-id: svn://svn.chromium.org/blink/trunk@178654 bbb929c8-8fbe-4397-9dbb-9b2b20218538