Allow setting constant bitrate flags in DefaultExtractorsFactory

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=207566605

RELEASENOTES.md

@@ -16,6 +16,9 @@
   * Support approximate seeking in AMR using a constant bitrate assumption.
     Note that the `FLAG_ENABLE_CONSTANT_BITRATE_SEEKING` flag must be set on the
     extractor to enable this functionality.
+  * Add `DefaultExtractorsFactory.setConstantBitrateSeekingEnabled` to enable
+    approximate seeking using a constant bitrate assumption for all extractors
+    that support it.
 * MPEG-TS: Support CEA-608/708 in H262
   ([#2565](https://github.com/google/ExoPlayer/issues/2565)).
 * MediaSession extension: Allow apps to set custom errors.

library/core/src/main/java/com/google/android/exoplayer2/extractor/DefaultExtractorsFactory.java

@@ -72,6 +72,9 @@ public final class DefaultExtractorsFactory implements ExtractorsFactory {
     FLAC_EXTRACTOR_CONSTRUCTOR = flacExtractorConstructor;
   }
 
+  private boolean constantBitrateSeekingEnabled;
+  private @AdtsExtractor.Flags int adtsFlags;
+  private @AmrExtractor.Flags int amrFlags;
   private @MatroskaExtractor.Flags int matroskaFlags;
   private @Mp4Extractor.Flags int mp4Flags;
   private @FragmentedMp4Extractor.Flags int fragmentedMp4Flags;
@@ -83,6 +86,45 @@ public final class DefaultExtractorsFactory implements ExtractorsFactory {
     tsMode = TsExtractor.MODE_SINGLE_PMT;
   }
 
+  /**
+   * Convenience method to set whether approximate seeking using constant bitrate assumptions should
+   * be enabled for all extractors that support it. If set to true, the flags required to enable
+   * this functionality will be OR'd with those passed to the setters when creating extractor
+   * instances. If set to false then the flags passed to the setters will be used without
+   * modification.
+   *
+   * @param constantBitrateSeekingEnabled Whether approximate seeking using a constant bitrate
+   *     assumption should be enabled for all extractors that support it.
+   */
+  public void setConstantBitrateSeekingEnabled(boolean constantBitrateSeekingEnabled) {
+    this.constantBitrateSeekingEnabled = constantBitrateSeekingEnabled;
+  }
+
+  /**
+   * Sets flags for {@link AdtsExtractor} instances created by the factory.
+   *
+   * @see AdtsExtractor#AdtsExtractor(long, int)
+   * @param flags The flags to use.
+   * @return The factory, for convenience.
+   */
+  public synchronized DefaultExtractorsFactory setAdtsExtractorFlags(
+      @AdtsExtractor.Flags int flags) {
+    this.adtsFlags = flags;
+    return this;
+  }
+
+  /**
+   * Sets flags for {@link AmrExtractor} instances created by the factory.
+   *
+   * @see AmrExtractor#AmrExtractor(int)
+   * @param flags The flags to use.
+   * @return The factory, for convenience.
+   */
+  public synchronized DefaultExtractorsFactory setAmrExtractorFlags(@AmrExtractor.Flags int flags) {
+    this.amrFlags = flags;
+    return this;
+  }
+
   /**
    * Sets flags for {@link MatroskaExtractor} instances created by the factory.
    *
@@ -165,15 +207,31 @@ public final class DefaultExtractorsFactory implements ExtractorsFactory {
     extractors[0] = new MatroskaExtractor(matroskaFlags);
     extractors[1] = new FragmentedMp4Extractor(fragmentedMp4Flags);
     extractors[2] = new Mp4Extractor(mp4Flags);
-    extractors[3] = new Mp3Extractor(mp3Flags);
+    extractors[3] =
-    extractors[4] = new AdtsExtractor();
+        new Mp3Extractor(
+            mp3Flags
+                | (constantBitrateSeekingEnabled
+                    ? Mp3Extractor.FLAG_ENABLE_CONSTANT_BITRATE_SEEKING
+                    : 0));
+    extractors[4] =
+        new AdtsExtractor(
+            /* firstStreamSampleTimestampUs= */ 0,
+            adtsFlags
+                | (constantBitrateSeekingEnabled
+                    ? AdtsExtractor.FLAG_ENABLE_CONSTANT_BITRATE_SEEKING
+                    : 0));
     extractors[5] = new Ac3Extractor();
     extractors[6] = new TsExtractor(tsMode, tsFlags);
     extractors[7] = new FlvExtractor();
     extractors[8] = new OggExtractor();
     extractors[9] = new PsExtractor();
     extractors[10] = new WavExtractor();
-    extractors[11] = new AmrExtractor();
+    extractors[11] =
+        new AmrExtractor(
+            amrFlags
+                | (constantBitrateSeekingEnabled
+                    ? AmrExtractor.FLAG_ENABLE_CONSTANT_BITRATE_SEEKING
+                    : 0));
     if (FLAC_EXTRACTOR_CONSTRUCTOR != null) {
       try {
         extractors[12] = FLAC_EXTRACTOR_CONSTRUCTOR.newInstance();