MediaPlayerBase: Add PlayerEventCallback#onSeekCompleted()

PlayerEventCallback#onSeekCompleted() will be called when the
MediaPlayerBase#seekTo() is completed. Following callbacks are also
added to listen the event.
  - SessionCallback#onSeekCompleted()
  - ControllerCallback#onSeekCompleted()

Bug: 74370608
Test: Build
Change-Id: Ib99a3cdfabe34378d0ea6b86a2ae1c9dd99c13c8

packages/MediaComponents/src/com/android/media/MediaController2Impl.java

@@ -808,6 +808,7 @@ public class MediaController2Impl implements MediaController2Provider {
         });
     }
 
+    // TODO(jaewan): Rename to seek completed
     void pushPositionChanges(final long eventTimeMs, final long positionMs) {
         synchronized (mLock) {
             mPositionEventTimeMs = eventTimeMs;
@@ -817,7 +818,7 @@ public class MediaController2Impl implements MediaController2Provider {
             if (!mInstance.isConnected()) {
                 return;
             }
-            mCallback.onPositionChanged(mInstance, eventTimeMs, positionMs);
+            mCallback.onSeekCompleted(mInstance, positionMs);
         });
     }
 

packages/MediaComponents/src/com/android/media/MediaSession2Stub.java

@@ -926,6 +926,7 @@ public class MediaSession2Stub extends IMediaSession2.Stub {
         });
     }
 
+    // TODO(jaewan): Rename
     public void notifyPositionChangedNotLocked(long eventTimeMs, long positionMs) {
         notifyAll((controller, iController) -> {
             iController.onPositionChanged(eventTimeMs, positionMs);