Link MediaSessionTabHelper with native MediaSession [CL is going to be split]

content/browser/web_contents/web_contents_android.cc

 // Copyright 2013 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/web_contents/web_contents_android.h"
 
 #include <stdint.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
+#include "base/memory/ptr_util.h"
 #include "base/json/json_writer.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "content/browser/accessibility/browser_accessibility_android.h"
 #include "content/browser/accessibility/browser_accessibility_manager_android.h"
 #include "content/browser/android/content_view_core_impl.h"
 #include "content/browser/android/interstitial_page_delegate_android.h"
 #include "content/browser/frame_host/interstitial_page_impl.h"
 #include "content/browser/media/android/browser_media_player_manager.h"
 #include "content/browser/media/android/media_web_contents_observer_android.h"
+#include "content/browser/media/session/media_session.h"
+#include "content/browser/media/session/media_session_delegate_android.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/devtools_messages.h"
 #include "content/common/frame_messages.h"
 #include "content/common/input_messages.h"
 #include "content/common/view_messages.h"
 #include "content/public/browser/android/app_web_message_port_service.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/message_port_provider.h"
@@ skipping 572 matching lines @@
   // base::Callback.
   ScopedJavaGlobalRef<jobject> j_callback;
   j_callback.Reset(env, callback);
 
   WebContentsImpl::AXTreeSnapshotCallback snapshot_callback =
       base::Bind(&AXTreeSnapshotCallback, j_callback);
   static_cast<WebContentsImpl*>(web_contents_)->RequestAXTreeSnapshot(
       snapshot_callback);
 }
 
-void WebContentsAndroid::ResumeMediaSession(JNIEnv* env,
-                                            const JavaParamRef<jobject>& obj) {
-  web_contents_->ResumeMediaSession();
-}
-
-void WebContentsAndroid::SuspendMediaSession(JNIEnv* env,
-                                             const JavaParamRef<jobject>& obj) {
-  web_contents_->SuspendMediaSession();
-}
-
-void WebContentsAndroid::StopMediaSession(JNIEnv* env,
-                                          const JavaParamRef<jobject>& obj) {
-  web_contents_->StopMediaSession();
+void WebContentsAndroid::AddMediaSessionDelegate(JNIEnv* env,
+                                                 const JavaParamRef<jobject>& obj,
+                                                 const JavaParamRef<jobject>& j_delegate) {
+  MediaSessionDelegateAndroid::CreateAndRegister(

[whywhat, 2016/10/20 15:38:33]

perhaps the delegates could be owned by WebContents?

[Zhiqiang Zhang (Slow), 2016/10/20 16:22:32]

I prefer not to pollute WebContents. Actually MediaSession has the same lifetime
as WebContents.

[whywhat, 2016/10/20 18:21:16]

Can we just own MSO in MediaSession and avoid using the observer pattern at all
then? You just register MSO with MS, it owns it and calls its methods. We don't
have cases of MSOs that are not owned by MS or that are owned but don't want to
observe the events right? If we do, I'll have to think more, perhaps :)

+      env, MediaSession::Get(web_contents()), j_delegate);
 }
 
 ScopedJavaLocalRef<jstring> WebContentsAndroid::GetEncoding(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj) const {
   return base::android::ConvertUTF8ToJavaString(env,
                                                 web_contents_->GetEncoding());
 }
 
 void WebContentsAndroid::GetContentBitmap(
@@ skipping 88 matching lines @@
     Java_WebContentsImpl_addToBitmapList(env, jbitmaps, jbitmap);
   }
   for (const gfx::Size& size : sizes) {
     Java_WebContentsImpl_createSizeAndAddToList(env, jsizes, size.width(),
                                                 size.height());
   }
   Java_WebContentsImpl_onDownloadImageFinished(
       env, *obj, *callback, id, http_status_code, jurl, jbitmaps, jsizes);
 }
 }  // namespace content