Fix #13283: restore volume immediately on audio focus gain

Replace the ValueAnimator-based animateAudio() call in onAudioFocusGain()
with a direct player.setVolume(1.0f). The ValueAnimator relies on the
Choreographer/main thread rendering loop, which is throttled or suspended
when the app is backgrounded (especially with battery optimizations on
Android 12+). This left the volume stuck at 0.2f until the user foregrounded
the app. Also remove setWillPauseWhenDucked(true) since the app ducks
volume rather than pausing, aligning the declared intent with actual behavior
so the system reliably delivers AUDIOFOCUS_GAIN on newer Android versions.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: utafrali

app/src/main/java/org/schabi/newpipe/player/helper/AudioReactor.java

@@ -1,8 +1,5 @@
 package org.schabi.newpipe.player.helper;
 
-import android.animation.Animator;
-import android.animation.AnimatorListenerAdapter;
-import android.animation.ValueAnimator;
 import android.content.Context;
 import android.content.Intent;
 import android.media.AudioManager;
@@ -21,7 +18,6 @@ public class AudioReactor implements AudioManager.OnAudioFocusChangeListener, An
 
     private static final String TAG = "AudioFocusReactor";
 
-    private static final int DUCK_DURATION = 1500;
     private static final float DUCK_AUDIO_TO = .2f;
 
     private static final int FOCUS_GAIN_TYPE = AudioManagerCompat.AUDIOFOCUS_GAIN;
@@ -42,7 +38,6 @@ public AudioReactor(@NonNull final Context context,
 
         request = new AudioFocusRequestCompat.Builder(FOCUS_GAIN_TYPE)
                 //.setAcceptsDelayedFocusGain(true)
-                .setWillPauseWhenDucked(true)
                 .setOnAudioFocusChangeListener(this)
                 .build();
     }
@@ -100,8 +95,7 @@ public void onAudioFocusChange(final int focusChange) {
 
     private void onAudioFocusGain() {
         Log.d(TAG, "onAudioFocusGain() called");
-        player.setVolume(DUCK_AUDIO_TO);
-        animateAudio(DUCK_AUDIO_TO, 1.0f);
+        player.setVolume(1.0f);
 
         if (PlayerHelper.isResumeAfterAudioFocusGain(context)) {
             player.play();
@@ -119,31 +113,6 @@ private void onAudioFocusLossCanDuck() {
         player.setVolume(DUCK_AUDIO_TO);
     }
 
-    private void animateAudio(final float from, final float to) {
-        final ValueAnimator valueAnimator = new ValueAnimator();
-        valueAnimator.setFloatValues(from, to);
-        valueAnimator.setDuration(AudioReactor.DUCK_DURATION);
-        valueAnimator.addListener(new AnimatorListenerAdapter() {
-            @Override
-            public void onAnimationStart(final Animator animation) {
-                player.setVolume(from);
-            }
-
-            @Override
-            public void onAnimationCancel(final Animator animation) {
-                player.setVolume(to);
-            }
-
-            @Override
-            public void onAnimationEnd(final Animator animation) {
-                player.setVolume(to);
-            }
-        });
-        valueAnimator.addUpdateListener(animation ->
-                player.setVolume(((float) animation.getAnimatedValue())));
-        valueAnimator.start();
-    }
-
     /*//////////////////////////////////////////////////////////////////////////
     // Audio Processing
     //////////////////////////////////////////////////////////////////////////*/