mediacodec: Don't suggest calling getOutputFormat() immediately

Calling getOutputFormat() at this point currently crashes in
native code. (After a fix to the native code, this gives an
IllegalStateException instead.)

Change-Id: Ia45c4820bb3d9ed435a0aeef1ff8c230524f2e1f

Author: mstorsjo

media/java/android/media/MediaCodec.java

@@ -33,7 +33,6 @@
  * codec.start();
  * ByteBuffer[] inputBuffers = codec.getInputBuffers();
  * ByteBuffer[] outputBuffers = codec.getOutputBuffers();
- * MediaFormat format = codec.getOutputFormat();
  * for (;;) {
  *   int inputBufferIndex = codec.dequeueInputBuffer(timeoutUs);
  *   if (inputBufferIndex >= 0) {
@@ -51,7 +50,7 @@
  *     outputBuffers = codec.getOutputBuffers();
  *   } else if (outputBufferIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
  *     // Subsequent data will conform to new format.
- *     format = codec.getOutputFormat();
+ *     MediaFormat format = codec.getOutputFormat();
  *     ...
  *   }
  * }