Make ProgressiveMediaExtractors public

So as for the user to be able to inject them.

PiperOrigin-RevId: 362056981

library/core/src/main/java/com/google/android/exoplayer2/source/BundledExtractorsAdapter.java

@@ -37,7 +37,7 @@ import java.util.Map;
  * {@link ProgressiveMediaExtractor} built on top of {@link Extractor} instances, whose
  * implementation classes are bundled in the app.
  */
-/* package */ final class BundledExtractorsAdapter implements ProgressiveMediaExtractor {
+public final class BundledExtractorsAdapter implements ProgressiveMediaExtractor {
 
   private final ExtractorsFactory extractorsFactory;
 

library/core/src/main/java/com/google/android/exoplayer2/source/MediaParserExtractorAdapter.java

@@ -38,7 +38,13 @@ import java.util.Map;
 
 /** {@link ProgressiveMediaExtractor} implemented on top of the platform's {@link MediaParser}. */
 @RequiresApi(30)
-/* package */ final class MediaParserExtractorAdapter implements ProgressiveMediaExtractor {
+public final class MediaParserExtractorAdapter implements ProgressiveMediaExtractor {
+
+  /**
+   * A {@link ProgressiveMediaExtractor.Factory} for instances of this class, which rely on platform
+   * extractors through {@link MediaParser}.
+   */
+  public static final ProgressiveMediaExtractor.Factory FACTORY = MediaParserExtractorAdapter::new;
 
   private final OutputConsumerAdapterV30 outputConsumerAdapter;
   private final InputReaderAdapterV30 inputReaderAdapter;