Fix proguard tests to use the instrumentation or app context as needed

The instrumentation context is needed to access assets bundled into
the **instrumenting** test APK.

Unfortunately the instrumentation context returns `null` from
`getApplicationContext()`, so we have to carefully only use it for
specifically loading the asset.

PiperOrigin-RevId: 875124490

Author: icbaker

libraries/test_proguard/src/androidTest/java/androidx/media3/test/proguard/ExtractorModuleProguardTest.java

@@ -15,26 +15,24 @@
  */
 package androidx.media3.test.proguard;
 
-import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
-import org.junit.Ignore;
+import androidx.test.platform.app.InstrumentationRegistry;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
 /** Unit test executing methods in {@link ExtractorModuleProguard}. */
 @RunWith(AndroidJUnit4.class)
-@Ignore("Fails on gradle: b/463675073")
 public final class ExtractorModuleProguardTest {
 
   @Test
   public void defaultExtractorFactory_createExtensionFlacExtractor_succeeds() throws Exception {
     ExtractorModuleProguard.createLibFlacExtractorWithDefaultExtractorsFactory(
-        ApplicationProvider.getApplicationContext());
+        InstrumentationRegistry.getInstrumentation().getContext());
   }
 
   @Test
   public void defaultExtractorFactory_createMidiExtractor_succeeds() throws Exception {
     ExtractorModuleProguard.createMidiExtractorWithDefaultExtractorsFactory(
-        ApplicationProvider.getApplicationContext());
+        InstrumentationRegistry.getInstrumentation().getContext());
   }
 }

libraries/test_proguard/src/androidTest/java/androidx/media3/test/proguard/UiModuleProguardTest.java

@@ -19,7 +19,7 @@
 import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
 
 import androidx.test.ext.junit.runners.AndroidJUnit4;
-import org.junit.Ignore;
+import androidx.test.platform.app.InstrumentationRegistry;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -46,10 +46,9 @@ public void playerView_inflateVideoDecoderGLSurfaceView_succeeds() {
   }
 
   @Test
-  @Ignore("Fails on gradle: b/463675073")
   public void playerControlView_scrubbingWithExoPlayer_succeeds() throws Exception {
     UiModuleProguard.scrubOnTimeBarWithExoPlayerAndCheckThatSuppressionReasonChangesAndSeeksHappen(
-        getApplicationContext());
+        InstrumentationRegistry.getInstrumentation().getContext(), getApplicationContext());
   }
 
   @Test

libraries/test_proguard/src/main/java/androidx/media3/test/proguard/UiModuleProguard.java

@@ -37,10 +37,12 @@
 import androidx.media3.common.TrackGroup;
 import androidx.media3.common.Tracks;
 import androidx.media3.common.util.ConditionVariable;
+import androidx.media3.datasource.AssetDataSource;
 import androidx.media3.exoplayer.BaseRenderer;
 import androidx.media3.exoplayer.ExoPlayer;
 import androidx.media3.exoplayer.Renderer;
 import androidx.media3.exoplayer.RendererCapabilities;
+import androidx.media3.exoplayer.source.DefaultMediaSourceFactory;
 import androidx.media3.exoplayer.video.VideoDecoderGLSurfaceView;
 import androidx.media3.exoplayer.video.spherical.SphericalGLSurfaceView;
 import androidx.media3.transformer.Composition;
@@ -87,7 +89,7 @@ public static void inflatePlayerViewWithVideoDecoderGLSurfaceView(Context contex
    * the suppression reason change and seeks happen.
    */
   public static void scrubOnTimeBarWithExoPlayerAndCheckThatSuppressionReasonChangesAndSeeksHappen(
-      Context context) throws InterruptedException {
+      Context instrumentationContext, Context applicationContext) throws InterruptedException {
     ConditionVariable playerReady = new ConditionVariable();
     List<@Player.PlaybackSuppressionReason Integer> playbackSuppressionReasons =
         Collections.synchronizedList(new ArrayList<>());
@@ -119,11 +121,20 @@ public void onPositionDiscontinuity(
     Handler mainHandler = new Handler(Looper.getMainLooper());
     mainHandler.post(
         () -> {
-          ExoPlayer player = new ExoPlayer.Builder(context).build();
+          ExoPlayer player =
+              new ExoPlayer.Builder(applicationContext)
+                  .setMediaSourceFactory(
+                      new DefaultMediaSourceFactory(
+                          // The asset media URI used below is accessible to the instrumentation
+                          // context, not the app context (which needs to be used for all other
+                          // purposes).
+                          /* dataSourceFactory= */ () ->
+                              new AssetDataSource(instrumentationContext)))
+                  .build();
           player.addListener(listener);
           PlayerControlView playerControlView =
               (PlayerControlView)
-                  LayoutInflater.from(context)
+                  LayoutInflater.from(applicationContext)
                       .inflate(
                           R.layout.player_control_view_with_scrubbable_timebar, /* root= */ null);
           playerControlView.setPlayer(player);