Keep TS packets with no continuity counter increase and no payload

This behavior is defined in ISO-13818-1, section 2.4.3.3(continuity_counter).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140029161

library/src/main/java/com/google/android/exoplayer2/extractor/ts/TsExtractor.java

@@ -216,9 +216,11 @@ public final class TsExtractor implements Extractor {
     int previousCounter = continuityCounters.get(pid, continuityCounter - 1);
     int previousCounter = continuityCounters.get(pid, continuityCounter - 1);
     continuityCounters.put(pid, continuityCounter);
     continuityCounters.put(pid, continuityCounter);
     if (previousCounter == continuityCounter) {
     if (previousCounter == continuityCounter) {
+      if (payloadExists) {
         // Duplicate packet found.
         // Duplicate packet found.
         tsPacketBuffer.setPosition(endOfPacket);
         tsPacketBuffer.setPosition(endOfPacket);
         return RESULT_CONTINUE;
         return RESULT_CONTINUE;
+      }
     } else if (continuityCounter != (previousCounter + 1) % 16) {
     } else if (continuityCounter != (previousCounter + 1) % 16) {
       discontinuityFound = true;
       discontinuityFound = true;
     }
     }