[dxvavda] Save information about outstanding buffers in hang minidumps.

media/gpu/dxva_video_decode_accelerator_win.h

Index: media/gpu/dxva_video_decode_accelerator_win.h
diff --git a/media/gpu/dxva_video_decode_accelerator_win.h b/media/gpu/dxva_video_decode_accelerator_win.h
index 2d990cfe66a27a4477c6a94e21888bb19aea9732..537ffa2e9f87e71c0516b91a46ce998d216574b5 100644
--- a/media/gpu/dxva_video_decode_accelerator_win.h
+++ b/media/gpu/dxva_video_decode_accelerator_win.h
@@ -463,6 +463,10 @@ class MEDIA_GPU_EXPORT DXVAVideoDecodeAccelerator
   // |pending_input_buffers_| is drained. Protected by |decoder_lock_|.
   bool sent_drain_message_;
 
+  // This is the array size of the D3D11 texture that's output to by the
+  // decoder. It's only used for debugging.
+  uint32_t output_array_size_ = 0;
+
   // List of input samples waiting to be processed.
   typedef std::list<base::win::ScopedComPtr<IMFSample>> PendingInputs;
   PendingInputs pending_input_buffers_;