Add getMetrics() API to MediaExtractorCompat

This method returns a `PersistableBundle` containing metrics data for the current media container. The bundle includes attributes and values for the media container, as described in `MediaExtractor.MetricsConstants`.

PiperOrigin-RevId: 696893276

libraries/exoplayer/src/androidTest/java/androidx/media3/exoplayer/MediaExtractorCompatTest.java

@@ -31,6 +31,7 @@ import android.media.metrics.LogSessionId;
 import android.media.metrics.MediaMetricsManager;
 import android.media.metrics.PlaybackSession;
 import android.net.Uri;
+import android.os.PersistableBundle;
 import androidx.media3.common.C;
 import androidx.media3.common.DrmInitData;
 import androidx.media3.common.Format;
@@ -49,6 +50,7 @@ import androidx.media3.extractor.SeekMap;
 import androidx.media3.extractor.SeekMap.SeekPoints;
 import androidx.media3.extractor.SeekPoint;
 import androidx.media3.extractor.TrackOutput;
+import androidx.media3.extractor.mp4.Mp4Extractor;
 import androidx.media3.test.utils.TestUtil;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
@@ -1002,6 +1004,27 @@ public class MediaExtractorCompatTest {
     assertThat(mediaExtractorCompat.hasCacheReachedEndOfStream()).isTrue();
   }
 
+  @Test
+  public void getMetrics_withMp4DataSource_returnsExpectedMetricsBundle() throws IOException {
+    assumeTrue(Util.SDK_INT >= 26);
+    // Needed to keep lint happy (it doesn't understand the assumeTrue call alone)
+    if (Util.SDK_INT < 26) {
+      return;
+    }
+    Context context = ApplicationProvider.getApplicationContext();
+    Uri contentUri = Uri.parse("asset:///media/mp4/sample.mp4");
+    MediaExtractorCompat mediaExtractorCompat = new MediaExtractorCompat(context);
+    mediaExtractorCompat.setDataSource(context, contentUri, /* headers= */ null);
+
+    PersistableBundle bundle = mediaExtractorCompat.getMetrics();
+
+    assertThat(bundle.getString(MediaExtractor.MetricsConstants.FORMAT))
+        .isEqualTo(Mp4Extractor.class.getSimpleName());
+    assertThat(bundle.getString(MediaExtractor.MetricsConstants.MIME_TYPE))
+        .isEqualTo(MimeTypes.VIDEO_MP4);
+    assertThat(bundle.getInt(MediaExtractor.MetricsConstants.TRACKS)).isEqualTo(2);
+  }
+
   // Internal methods.
 
   private void assertReadSample(int trackIndex, long timeUs, int size, byte... sampleData) {

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/MediaExtractorCompat.java

@@ -30,6 +30,7 @@ import android.media.MediaExtractor;
 import android.media.MediaFormat;
 import android.media.metrics.LogSessionId;
 import android.net.Uri;
+import android.os.PersistableBundle;
 import android.util.SparseArray;
 import androidx.annotation.IntDef;
 import androidx.annotation.Nullable;
@@ -657,6 +658,30 @@ public final class MediaExtractorCompat {
     return getCachedDuration() == 0;
   }
 
+  /**
+   * Returns a {@link PersistableBundle} containing metrics data for the current media container.
+   *
+   * <p>The bundle includes attributes and values for the media container, as described in {@link
+   * MediaExtractor.MetricsConstants}.
+   */
+  @RequiresApi(26)
+  public PersistableBundle getMetrics() {
+    PersistableBundle bundle = new PersistableBundle();
+    if (currentExtractor != null) {
+      bundle.putString(
+          MediaExtractor.MetricsConstants.FORMAT,
+          currentExtractor.getUnderlyingImplementation().getClass().getSimpleName());
+    }
+    if (!tracks.isEmpty()) {
+      Format format = tracks.get(0).getFormat(formatHolder, noDataBuffer);
+      if (format.containerMimeType != null) {
+        bundle.putString(MediaExtractor.MetricsConstants.MIME_TYPE, format.containerMimeType);
+      }
+    }
+    bundle.putInt(MediaExtractor.MetricsConstants.TRACKS, tracks.size());
+    return bundle;
+  }
+
   @VisibleForTesting(otherwise = NONE)
   public Allocator getAllocator() {
     return allocator;