Implement MediaMetadata artwork in content

content/renderer/media/android/renderer_media_session_manager.cc

Index: content/renderer/media/android/renderer_media_session_manager.cc
diff --git a/content/renderer/media/android/renderer_media_session_manager.cc b/content/renderer/media/android/renderer_media_session_manager.cc
index b5331c7472a30cacc4582ef5b350b0a0c67a6615..7a06f7a6b29a62c8a6edc111bee1c03f7c48d2ec 100644
--- a/content/renderer/media/android/renderer_media_session_manager.cc
+++ b/content/renderer/media/android/renderer_media_session_manager.cc
@@ -73,6 +73,8 @@ void RendererMediaSessionManager::SetMetadata(
       metadata.artist.substr(0, MediaMetadata::kMaxIPCStringLength);
   ipc_metadata.album =
       metadata.album.substr(0, MediaMetadata::kMaxIPCStringLength);
+  // TODO(zqzhang): apply sanity checks on artwork?

[palmer, 2016/06/14 22:06:31]

Yes, please. :) For example, is the src valid? (What is it supposed to be? A
URL? If so, are there aspects of the URL you can check for, such as is it
parseable, does it use an approved scheme (e.g. not telnet: or mailto:), et c.?)

Similarly, are its sizes reasonable? A rectangle that is 2 billion x 2 billion
pixels is probably questionable, for example. That kind of thing.

[Zhiqiang Zhang (Slow), 2016/06/20 18:26:49]

Now I'm doing sanity checks (is_valid(), IsStandard(), SchemeIsHttpOrHttps(),
SchemeIsFile()).

For type, I'm just truncating the string if it's too long.

For sizes, I'm removing the sizes that are negative or too large.

+  ipc_metadata.artwork = metadata.artwork;
 
   Send(new MediaSessionHostMsg_SetMetadata(routing_id(),
                                            session_id,