Merge "Fix a typo in the sample code" into jb-mr1-dev

Author: Teng-Hui Zhu

media/java/android/media/MediaExtractor.java

@@ -45,7 +45,7 @@
  * }
  * ByteBuffer inputBuffer = ByteBuffer.allocate(...)
  * while (extractor.readSampleData(inputBuffer, ...) >= 0) {
- *   int trackIndex = extractor.getTrackIndex();
+ *   int trackIndex = extractor.getSampleTrackIndex();
  *   long presentationTimeUs = extractor.getSampleTime();
  *   ...
  *   extractor.advance();