Wrap MediaMetadata in base::Optional in content and chrome

content/browser/media/session/media_session_browsertest.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/browser/media/session/media_session.h"
 
 #include <stddef.h>
 
 #include <list>
 #include <vector>
@@ skipping 36 matching lines @@
   }
 };
 
 class MockWebContentsObserver : public WebContentsObserver {
  public:
   MockWebContentsObserver(WebContents* web_contents)
       : WebContentsObserver(web_contents) {}
 
   MOCK_METHOD3(MediaSessionStateChanged,
                void(bool is_controllable, bool is_suspended,
-                    const content::MediaMetadata& metadata));
+                    const base::Optional<content::MediaMetadata>& metadata));
 };
 
 }  // namespace
 
 class MediaSessionBrowserTest : public content::ContentBrowserTest {
  protected:
   MediaSessionBrowserTest() = default;
 
   void SetUpOnMainThread() override {
     ContentBrowserTest::SetUpOnMainThread();
@@ skipping 1270 matching lines @@
                  media::MediaContentType::Persistent);
   clock->Advance(base::TimeDelta::FromMilliseconds(1000));
   media_session_->Stop(MediaSession::SuspendType::UI);
 
   std::unique_ptr<base::HistogramSamples> samples(
       tester.GetHistogramSamplesSinceCreation("Media.Session.ActiveTime"));
   EXPECT_EQ(2, samples->TotalCount());
   EXPECT_EQ(1, samples->GetCount(1000));
   EXPECT_EQ(1, samples->GetCount(10000));
 }