[Android] A prototype of the interactive media notification.

content/browser/media/android/media_session.cc

Index: content/browser/media/android/media_session.cc
diff --git a/content/browser/media/android/media_session.cc b/content/browser/media/android/media_session.cc
index a19e29eab89236838194ace2b349ad64c8183674..2d7ea09db225836f6391dd4d3bcb4a3dc2b8023e 100644
--- a/content/browser/media/android/media_session.cc
+++ b/content/browser/media/android/media_session.cc
@@ -6,6 +6,8 @@
 
 #include "base/android/jni_android.h"
 #include "content/browser/media/android/media_session_observer.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/browser/web_contents_delegate.h"
 #include "jni/MediaSession_jni.h"
 
 namespace content {
@@ -68,6 +70,7 @@ bool MediaSession::AddPlayer(MediaSessionObserver* observer,
   State old_audio_focus_state = audio_focus_state_;
   audio_focus_state_ = RequestSystemAudioFocus(type) ? State::Active
                                                      : State::Suspended;
+  Type old_audio_focus_type = audio_focus_type_;
   audio_focus_type_ = type;
 
   if (audio_focus_state_ != State::Active)
@@ -75,10 +78,16 @@ bool MediaSession::AddPlayer(MediaSessionObserver* observer,
 
   // The session should be reset if a player is starting while all players are
   // suspended.
-  if (old_audio_focus_state != State::Active)
+  if (old_audio_focus_state != State::Active) {
+    // Hide the controls if the type switched from Content to Transient.
+    if (audio_focus_type_ == Type::Transient &&
+        old_audio_focus_type == Type::Content)
+      UpdateMediaControls();

[mlamouri (slow - plz ping), 2015/06/24 16:15:02]

With the new model of calling UpdateMediaControls() which the MediaControls
checking its visibility and playing state, I do not think you need that call.

[whywhat, 2015/06/24 18:36:15]

Indeed. Done.

     players_.clear();
+  }
 
   players_.insert(PlayerIdentifier(observer, player_id));
+  UpdateMediaControls();
 
   return true;
 }
@@ -104,11 +113,35 @@ void MediaSession::RemovePlayers(MediaSessionObserver* observer) {
 }
 
 void MediaSession::OnSuspend(JNIEnv* env, jobject obj, jboolean temporary) {
-  OnSuspend(temporary);
+  OnSuspendInternal(temporary);
+  UpdateMediaControls();
 }
 
 void MediaSession::OnResume(JNIEnv* env, jobject obj) {
-  OnResume();
+  OnResumeInternal();
+  UpdateMediaControls();
+}
+
+void MediaSession::OnControlsPause() {
+  DCHECK(!IsPaused());
+
+  // Since the playback can be resumed, it's a transient suspension.
+  OnSuspendInternal(true);
+}
+
+void MediaSession::OnControlsResume() {
+  DCHECK(IsPaused());
+
+  OnResumeInternal();
+}
+
+bool MediaSession::IsPaused() {
+  return audio_focus_state_ != State::Active;
+}
+
+bool MediaSession::IsControllable() {
+  return audio_focus_state_ != State::Suspended &&
+      audio_focus_type_ == Type::Content;
 }
 
 void MediaSession::ResetJavaRefForTest() {
@@ -123,7 +156,12 @@ MediaSession::Type MediaSession::audio_focus_type_for_test() const {
   return audio_focus_type_;
 }
 
-void MediaSession::OnSuspend(bool temporary) {
+void MediaSession::RemoveAllPlayersForTest() {
+  players_.clear();
+  AbandonSystemAudioFocusIfNeeded();
+}
+
+void MediaSession::OnSuspendInternal(bool temporary) {
   if (temporary)
     audio_focus_state_ = State::TemporarilySuspended;
   else
@@ -133,7 +171,7 @@ void MediaSession::OnSuspend(bool temporary) {
     it.observer->OnSuspend(it.player_id);
 }
 
-void MediaSession::OnResume() {
+void MediaSession::OnResumeInternal() {
   audio_focus_state_ = State::Active;
 
   for (const auto& it : players_)
@@ -178,6 +216,12 @@ void MediaSession::AbandonSystemAudioFocusIfNeeded() {
   }
 
   audio_focus_state_ = State::Suspended;
+  UpdateMediaControls();
+}
+
+void MediaSession::UpdateMediaControls() {
+  if (web_contents()->GetDelegate())
+    web_contents()->GetDelegate()->UpdateMediaControls(web_contents());
 }
 
 }  // namespace content