[MediaSession] Record when media session ducks

We now lower the volume instead of suspend the media session when we
receiving AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK. However we still want to
record the event in the UMA.

BUG=580494

Review URL: https://codereview.chromium.org/1685183002

Cr-Commit-Position: refs/heads/master@{#375612}

3 files changed, 12 insertions, 0 deletions

diff --git a/content/browser/media/android/media_session.cc b/content/browser/media/android/media_session.cc
index e90daf4..1732105 100644
--- a/content/browser/media/android/media_session.cc
+++ b/content/browser/media/android/media_session.cc
@@ -136,6 +136,12 @@ void MediaSession::OnResume(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   OnResumeInternal(SuspendType::SYSTEM);
 }
 
+void MediaSession::RecordSessionDuck(JNIEnv* env,
+                                     const JavaParamRef<jobject>& obj) {
+  uma_helper_.RecordSessionSuspended(
+      MediaSessionSuspendedSource::SystemTransientDuck);
+}
+
 void MediaSession::OnPlayerPaused(MediaSessionObserver* observer,
                                   int player_id) {
   // If a playback is completed, BrowserMediaPlayerManager will call
diff --git a/content/browser/media/android/media_session.h b/content/browser/media/android/media_session.h
index b0a1157..1271124 100644
--- a/content/browser/media/android/media_session.h
+++ b/content/browser/media/android/media_session.h
@@ -77,6 +77,11 @@ class CONTENT_EXPORT MediaSession
   // Called by Java through JNI.
   void OnResume(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
 
+  // Called when the Android system requests the MediaSession to duck.
+  // Called by Java through JNI.
+  void RecordSessionDuck(JNIEnv* env,
+                         const base::android::JavaParamRef<jobject> &obj);
+
   // Called when a player is paused in the content.
   // If the paused player is the last player, we suspend the MediaSession.
   // Otherwise, the paused player will be removed from the MediaSession.
diff --git a/content/browser/media/android/media_session_uma_helper.h b/content/browser/media/android/media_session_uma_helper.h
index 69fbaa9..1fcf6b5 100644
--- a/content/browser/media/android/media_session_uma_helper.h
+++ b/content/browser/media/android/media_session_uma_helper.h
@@ -24,6 +24,7 @@ class CONTENT_EXPORT MediaSessionUmaHelper {
     SystemPermanent = 1,
     UI = 2,
     CONTENT = 3,
+    SystemTransientDuck = 4,
     Count // Leave at the end.
   };