Wrap MediaMetadata in base::Optional in content and chrome

content/renderer/media/android/renderer_media_session_manager.cc

 // Copyright 2015 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 "content/renderer/media/android/renderer_media_session_manager.h"
 
 #include "base/logging.h"
 #include "content/common/media/media_metadata_sanitizer.h"
 #include "content/common/media/media_session_messages_android.h"
 #include "content/public/common/media_metadata.h"
@@ skipping 46 matching lines @@
 
 void RendererMediaSessionManager::Deactivate(
     int session_id,
     std::unique_ptr<blink::WebMediaSessionDeactivateCallback> callback) {
   int request_id = pending_deactivation_requests_.Add(callback.release());
   Send(
       new MediaSessionHostMsg_Deactivate(routing_id(), session_id, request_id));
 }
 
 void RendererMediaSessionManager::SetMetadata(
-    int session_id,
-    const MediaMetadata& metadata) {
+    int session_id, const base::Optional<MediaMetadata>& metadata) {
 
   // TODO(zqzhang): print a console warning when metadata is dirty. See
   // https://crbug.com/625244.
   Send(new MediaSessionHostMsg_SetMetadata(
       routing_id(), session_id,
-      MediaMetadataSanitizer::CheckSanity(metadata) ?
-      metadata : MediaMetadataSanitizer::Sanitize(metadata)));
+      (!metadata || MediaMetadataSanitizer::CheckSanity(metadata.value()))

[mlamouri (slow - plz ping), 2016/09/01 17:47:49]

Maybe `!metadata.has_value()` instead of `!metadata`?

[Zhiqiang Zhang (Slow), 2016/09/02 12:11:41]

Done.

+      ? metadata
+      : MediaMetadataSanitizer::Sanitize(metadata.value())));
 }
 
 void RendererMediaSessionManager::OnDidActivate(int request_id, bool success) {
   DCHECK(pending_activation_requests_.Lookup(request_id)) << request_id;
   blink::WebMediaSessionActivateCallback* callback =
       pending_activation_requests_.Lookup(request_id);
   if (success) {
     callback->onSuccess();
   } else {
     callback->onError(
         blink::WebMediaSessionError(blink::WebMediaSessionError::Activate));
   }
   pending_activation_requests_.Remove(request_id);
 }
 
 void RendererMediaSessionManager::OnDidDeactivate(int request_id) {
   DCHECK(pending_deactivation_requests_.Lookup(request_id)) << request_id;
   pending_deactivation_requests_.Lookup(request_id)->onSuccess();
   pending_deactivation_requests_.Remove(request_id);
 }
 
 }  // namespace content