Fix intermittent decoder crash when playing MP3 inside MP4

library/src/main/java/com/google/android/exoplayer/extractor/mp3/Mp3Extractor.java

@@ -30,7 +30,6 @@ import com.google.android.exoplayer.util.Util;
 
 import java.io.EOFException;
 import java.io.IOException;
-import java.util.Collections;
 
 /**
  * Extracts data from an MP3 file.
@@ -247,7 +246,7 @@ public final class Mp3Extractor implements Extractor {
       extractorOutput.seekMap(seeker);
       trackOutput.format(MediaFormat.createAudioFormat(synchronizedHeader.mimeType,
           MpegAudioHeader.MAX_FRAME_SIZE_BYTES, seeker.getDurationUs(), synchronizedHeader.channels,
-          synchronizedHeader.sampleRate, Collections.<byte[]>emptyList()));
+          synchronizedHeader.sampleRate, null));
     }
 
     return headerPosition;

library/src/main/java/com/google/android/exoplayer/extractor/mp4/AtomParsers.java

@@ -471,8 +471,7 @@ import java.util.List;
       }
     }
 
-    List<byte[]> initializationData = csdLength == 0 ? Collections.<byte[]>emptyList()
-        : Collections.singletonList(buffer);
+    List<byte[]> initializationData = csdLength == 0 ? null : Collections.singletonList(buffer);
     return Pair.create(initializationData, lengthSizeMinusOne + 1);
   }
 
@@ -628,6 +627,10 @@ import java.util.List;
     int objectTypeIndication = parent.readUnsignedByte();
     String mimeType;
     switch (objectTypeIndication) {
+      case 0x6B:
+        mimeType = MimeTypes.AUDIO_MPEG;
+        // Don't extract codec-specific data for MPEG audio tracks, as it is not needed.
+        return Pair.create(mimeType, null);
       case 0x20:
         mimeType = MimeTypes.VIDEO_MP4V;
         break;
@@ -640,9 +643,6 @@ import java.util.List;
       case 0x40:
         mimeType = MimeTypes.AUDIO_AAC;
         break;
-      case 0x6B:
-        mimeType = MimeTypes.AUDIO_MPEG;
-        break;
       case 0xA5:
         mimeType = MimeTypes.AUDIO_AC3;
         break;

library/src/main/java/com/google/android/exoplayer/extractor/ts/MpegAudioReader.java

@@ -21,8 +21,6 @@ import com.google.android.exoplayer.extractor.TrackOutput;
 import com.google.android.exoplayer.util.MpegAudioHeader;
 import com.google.android.exoplayer.util.ParsableByteArray;
 
-import java.util.Collections;
-
 /**
  * Parses a continuous MPEG Audio byte stream and extracts individual frames.
  */
@@ -164,7 +162,7 @@ import java.util.Collections;
       frameDurationUs = (C.MICROS_PER_SECOND * header.samplesPerFrame) / header.sampleRate;
       MediaFormat mediaFormat = MediaFormat.createAudioFormat(header.mimeType,
           MpegAudioHeader.MAX_FRAME_SIZE_BYTES, C.UNKNOWN_TIME_US, header.channels,
-          header.sampleRate, Collections.<byte[]>emptyList());
+          header.sampleRate, null);
       output.format(mediaFormat);
       hasOutputFormat = true;
     }

library/src/main/java/com/google/android/exoplayer/util/Ac3Util.java

@@ -17,8 +17,6 @@ package com.google.android.exoplayer.util;
 
 import com.google.android.exoplayer.MediaFormat;
 
-import java.util.Collections;
-
 /**
  * Utility methods for parsing AC-3 headers.
  */
@@ -51,7 +49,7 @@ public final class Ac3Util {
       channelCount++;
     }
     return MediaFormat.createAudioFormat(MimeTypes.AUDIO_AC3, MediaFormat.NO_VALUE,
-        channelCount, sampleRate, Collections.<byte[]>emptyList());
+        channelCount, sampleRate, null);
   }
 
   /**
@@ -74,7 +72,7 @@ public final class Ac3Util {
       channelCount++;
     }
     return MediaFormat.createAudioFormat(MimeTypes.AUDIO_EC3, MediaFormat.NO_VALUE,
-        channelCount, sampleRate, Collections.<byte[]>emptyList());
+        channelCount, sampleRate, null);
   }
 
   /**
@@ -102,8 +100,7 @@ public final class Ac3Util {
     }
     boolean lfeon = data.readBit();
     return MediaFormat.createAudioFormat(MimeTypes.AUDIO_AC3, MediaFormat.NO_VALUE,
-        CHANNEL_COUNTS[acmod] + (lfeon ? 1 : 0), SAMPLE_RATES[fscod],
-        Collections.<byte[]>emptyList());
+        CHANNEL_COUNTS[acmod] + (lfeon ? 1 : 0), SAMPLE_RATES[fscod], null);
   }
 
   /**