Try again to merge branch 'frame-parallel' into master branch.

In frame parallel decode, libvpx decoder decodes several frames on all
cpus in parallel fashion. If not being flushed, it will only return frame
when all the cpus are busy. If getting flushed, it will return all the
frames in the decoder. Compare with current serial decode mode in which
libvpx decoder is idle between decode calls, libvpx decoder is busy
between decode calls.

Current frame parallel decode will only speed up the decoding for frame
parallel encoded videos. For non frame parallel encoded videos, frame
parallel decode is slower than serial decode due to lack of loopfilter
worker thread.

There are still some known issues that need to be addressed. For example:
decode frame parallel videos with segmentation enabled is not right sometimes.

* frame-parallel:
  Add error handling for frame parallel decode and unit test for that.
  Fix a bug in frame parallel decode and add a unit test for that.
  Add two test vectors to test frame parallel decode.
  Add key frame seeking to webmdec and webm_video_source.
  Implement frame parallel decode for VP9.
  Increase the thread test range to cover 5, 6, 7, 8 threads.
  Fix a bug in adding frame parallel unit test.
  Add VP9 frame-parallel unit test.
  Manually pick "Make the api behavior conform to api spec." from master branch.
  Move vp9_dec_build_inter_predictors_* to decoder folder.
  Add segmentation map array for current and last frame segmentation.
  Include the right header for VP9 worker thread.
  Move vp9_thread.* to common.
  ctrl_get_reference does not need user_priv.
  Seperate the frame buffers from VP9 encoder/decoder structure.
  Revert "Revert "Revert "Revert 3 patches from Hangyu to get Chrome to build:"""
 Conflicts:
       test/codec_factory.h
       test/decode_test_driver.cc
       test/decode_test_driver.h
       test/invalid_file_test.cc
       test/test-data.sha1
       test/test.mk
       test/test_vectors.cc
       vp8/vp8_dx_iface.c
       vp9/common/vp9_alloccommon.c
       vp9/common/vp9_entropymode.c
       vp9/common/vp9_loopfilter_thread.c
       vp9/common/vp9_loopfilter_thread.h
       vp9/common/vp9_mvref_common.c
       vp9/common/vp9_onyxc_int.h
       vp9/common/vp9_reconinter.c
       vp9/decoder/vp9_decodeframe.c
       vp9/decoder/vp9_decodeframe.h
       vp9/decoder/vp9_decodemv.c
       vp9/decoder/vp9_decoder.c
       vp9/decoder/vp9_decoder.h
       vp9/encoder/vp9_encoder.c
       vp9/encoder/vp9_pickmode.c
       vp9/encoder/vp9_rdopt.c
       vp9/vp9_cx_iface.c
       vp9/vp9_dx_iface.c

This reverts commit a18da9760a.

Change-Id: I361442ffec1586d036ea2e0ee97ce4f077585f02

vp9/decoder/vp9_decoder.h

@@ -19,6 +19,7 @@
 #include "vp9/common/vp9_onyxc_int.h"
 #include "vp9/common/vp9_ppflags.h"
 #include "vp9/common/vp9_thread.h"
+#include "vp9/decoder/vp9_dthread.h"
 #include "vp9/decoder/vp9_reader.h"
 
 #ifdef __cplusplus
@@ -33,7 +34,7 @@ typedef struct TileData {
 } TileData;
 
 typedef struct TileWorkerData {
-  VP9_COMMON *cm;
+  struct VP9Decoder *pbi;
   vp9_reader bit_reader;
   DECLARE_ALIGNED(16, MACROBLOCKD, xd);
   struct vpx_internal_error_info error_info;
@@ -50,6 +51,12 @@ typedef struct VP9Decoder {
 
   int frame_parallel_decode;  // frame-based threading.
 
+  // TODO(hkuang): Combine this with cur_buf in macroblockd as they are
+  // the same.
+  RefCntBuffer *cur_buf;   //  Current decoding frame buffer.
+  RefCntBuffer *prev_buf;  //  Previous decoding frame buffer.
+
+  VP9Worker *frame_worker_owner;   // frame_worker that owns this pbi.
   VP9Worker lf_worker;
   VP9Worker *tile_workers;
   TileWorkerData *tile_worker_data;
@@ -66,7 +73,8 @@ typedef struct VP9Decoder {
 
   int max_threads;
   int inv_tile_order;
-  int need_resync;  // wait for key/intra-only frame
+  int need_resync;  // wait for key/intra-only frame.
+  int hold_ref_buf;  // hold the reference buffer.
 } VP9Decoder;
 
 int vp9_receive_compressed_data(struct VP9Decoder *pbi,
@@ -83,10 +91,6 @@ vpx_codec_err_t vp9_set_reference_dec(VP9_COMMON *cm,
                                       VP9_REFFRAME ref_frame_flag,
                                       YV12_BUFFER_CONFIG *sd);
 
-struct VP9Decoder *vp9_decoder_create();
-
-void vp9_decoder_remove(struct VP9Decoder *pbi);
-
 static INLINE uint8_t read_marker(vpx_decrypt_cb decrypt_cb,
                                   void *decrypt_state,
                                   const uint8_t *data) {
@@ -106,6 +110,25 @@ vpx_codec_err_t vp9_parse_superframe_index(const uint8_t *data,
                                            vpx_decrypt_cb decrypt_cb,
                                            void *decrypt_state);
 
+struct VP9Decoder *vp9_decoder_create(BufferPool *const pool);
+
+void vp9_decoder_remove(struct VP9Decoder *pbi);
+
+static INLINE void decrease_ref_count(int idx, RefCntBuffer *const frame_bufs,
+                                      BufferPool *const pool) {
+  if (idx >= 0) {
+    --frame_bufs[idx].ref_count;
+    // A worker may only get a free framebuffer index when calling get_free_fb.
+    // But the private buffer is not set up until finish decoding header.
+    // So any error happens during decoding header, the frame_bufs will not
+    // have valid priv buffer.
+    if (frame_bufs[idx].ref_count == 0 &&
+        frame_bufs[idx].raw_frame_buffer.priv) {
+      pool->release_fb_cb(pool->cb_priv, &frame_bufs[idx].raw_frame_buffer);
+    }
+  }
+}
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif