Merge remote-tracking branch 'qatar/master'

* qatar/master: (35 commits)
  libopencore-amr: check output buffer size before decoding
  libopencore-amr: remove unneeded buf_size==0 check.
  libopencore-amr: remove unneeded frame_count field.
  aac_latm: remove unneeded check for zero-size packet.
  pcmdec: fix output buffer size check by calculating the actual output size prior to decoding.
  pcmdec: move codec-specific variable declarations to the corresponding codec blocks.
  pcmdec: return buf_size instead of src-buf.
  avcodec: remove the Zork PCM encoder.
  pcm_zork: use AV_SAMPLE_FMT_U8 instead of shifting all samples by 8.
  pcmenc: remove unneeded sample_fmt check.
  pcmdec: move number of channels check to pcm_decode_init()
  pcmdec: remove unnecessary check for sample_fmt change
  pcmdec: move DVD PCM bits_per_coded_sample check near to the code that sets the sample size.
  pcmdec: do not needlessly set *data_size to 0
  alacdec: remove unneeded NULL or zero-size packet checks.
  alacdec: simplify buffer allocation by using FF_ALLOC_OR_GOTO()
  alacdec: ask for a sample for unsupported sample depths.
  alacdec: cosmetics: use 'ch' instead of 'chan' to iterate channels
  alacdec: move some declarations to the top of the function
  alacdec: always use get_sbits_long() for uncompressed samples
  ...

Conflicts:
	libavcodec/pcm.c
	tests/ref/acodec/pcm

Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/pthread.c

@@ -686,6 +686,7 @@ static void frame_thread_free(AVCodecContext *avctx, int thread_count)
     av_freep(&fctx->threads);
     pthread_mutex_destroy(&fctx->buffer_mutex);
     av_freep(&avctx->thread_opaque);
+    avctx->has_b_frames -= avctx->thread_count - 1;
 }
 
 static int frame_thread_init(AVCodecContext *avctx)