Reset camera motion rotation when camera motion track is disabled

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=210696525

library/core/src/main/java/com/google/android/exoplayer2/video/spherical/CameraMotionListener.java

@@ -27,6 +27,6 @@ public interface CameraMotionListener {
    */
   void onCameraMotion(long timeUs, float[] rotation);
 
-  /** Called when the camera motion track position is reset. */
+  /** Called when the camera motion track position is reset or the track is disabled. */
   void onCameraMotionReset();
 }

library/core/src/main/java/com/google/android/exoplayer2/video/spherical/CameraMotionRenderer.java

@@ -72,15 +72,12 @@ public class CameraMotionRenderer extends BaseRenderer {
 
   @Override
   protected void onPositionReset(long positionUs, boolean joining) throws ExoPlaybackException {
-    lastTimestampUs = 0;
-    if (listener != null) {
-      listener.onCameraMotionReset();
-    }
+    reset();
   }
 
   @Override
   protected void onDisabled() {
-    lastTimestampUs = 0;
+    reset();
   }
 
   @Override
@@ -126,4 +123,11 @@ public class CameraMotionRenderer extends BaseRenderer {
     }
     return result;
   }
+
+  private void reset() {
+    lastTimestampUs = 0;
+    if (listener != null) {
+      listener.onCameraMotionReset();
+    }
+  }
 }