Fixes animation video from not playing after onStop

Adds a pause command that doesn't destroy the video surface, and calls
onStop when we want to destroy the media player.

bug:26516460
Change-Id: If46d26088e81fdca6a73a663a48901bb5245acc8

src/com/android/settings/fingerprint/FingerprintLocationAnimationVideoView.java

@@ -117,11 +117,18 @@ public class FingerprintLocationAnimationVideoView extends TextureView
 
     @Override
     public void stopAnimation() {
-        if (mMediaPlayer != null && mMediaPlayer.isPlaying()) {
+        if (mMediaPlayer != null) {
             mMediaPlayer.stop();
             mMediaPlayer.release();
             mMediaPlayer = null;
         }
     }
 
+    @Override
+    public void pauseAnimation() {
+        if (mMediaPlayer != null && mMediaPlayer.isPlaying()) {
+            mMediaPlayer.pause();
+        }
+    }
+
 }