Fix Vaapi VDA flush handling during resolution change

media/gpu/vaapi_video_decode_accelerator.h

Index: media/gpu/vaapi_video_decode_accelerator.h
diff --git a/media/gpu/vaapi_video_decode_accelerator.h b/media/gpu/vaapi_video_decode_accelerator.h
index 8228a928cfdbc5d756982351abd39a408bf34a65..b4f306bff0802d897041ae22fe17932b34b9bbeb 100644
--- a/media/gpu/vaapi_video_decode_accelerator.h
+++ b/media/gpu/vaapi_video_decode_accelerator.h
@@ -93,7 +93,7 @@ class MEDIA_GPU_EXPORT VaapiVideoDecodeAccelerator
 
   // Map the received input buffer into this process' address space and
   // queue it for decode.
-  void MapAndQueueNewInputBuffer(const BitstreamBuffer& bitstream_buffer);
+  bool MapAndQueueNewInputBuffer(const BitstreamBuffer& bitstream_buffer);
 
   // Get a new input buffer from the queue and set it up in decoder. This will
   // sleep if no input buffers are available. Return true if a new buffer has
@@ -110,6 +110,8 @@ class MEDIA_GPU_EXPORT VaapiVideoDecodeAccelerator
   // reset/flush/destroy).
   bool WaitForSurfaces_Locked();
 
+  bool IsFlushPending_Locked();
+
   // Continue decoding given input buffers and sleep waiting for input/output
   // as needed. Will exit if a new set of surfaces or reset/flush/destroy
   // is requested.
@@ -196,8 +198,6 @@ class MEDIA_GPU_EXPORT VaapiVideoDecodeAccelerator
     kDecoding,
     // Resetting, waiting for decoder to finish current task and cleanup.
     kResetting,
-    // Flushing, waiting for decoder to finish current task and cleanup.
-    kFlushing,
     // Idle, decoder in state ready to start/resume decoding.
     kIdle,
     // Destroying, waiting for the decoder to finish current task.
@@ -214,7 +214,11 @@ class MEDIA_GPU_EXPORT VaapiVideoDecodeAccelerator
     InputBuffer();

[Owen Lin, 2017/01/19 07:39:16]

Remove both ctor and dtor?

[kcwu, 2017/01/20 07:49:03]

Done.

     ~InputBuffer();
 
-    int32_t id;
+    // Indicates this is a dummy buffer for flush request.
+    // If |dummy_flush| is true, |id| and |shm| are not used.
+    bool dummy_flush = false;
+
+    int32_t id = 0;
     std::unique_ptr<SharedMemoryRegion> shm;

[Owen Lin, 2017/01/19 07:39:16]

Why not just use "shm == null" to indicate an empty buffer?

[kcwu, 2017/01/19 08:26:10]

Do you mean "shm = null" to assign a default value? If so, it's unnecessary.

[Owen Lin, 2017/01/20 02:20:06]

No, I mean we don't really need a new member dummy_flush but using shm == null
to indicate an empty buffer. But it's really up to you.

[kcwu, 2017/01/20 07:49:03]

Done.

   };