V4L2SVDA: Add a VP9Accelerator implementation utilizing the V4L2 VP9 frame API.

media/gpu/vp9_decoder.h

Index: media/gpu/vp9_decoder.h
diff --git a/media/gpu/vp9_decoder.h b/media/gpu/vp9_decoder.h
index b262f14af95a7565113d3c47fcac7bb39625b147..d2264b595f42b6544bc85377cdc2d1b777e8ba75 100644
--- a/media/gpu/vp9_decoder.h
+++ b/media/gpu/vp9_decoder.h
@@ -11,6 +11,7 @@
 #include <memory>
 #include <vector>
 
+#include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "media/filters/vp9_parser.h"
@@ -48,20 +49,22 @@ class MEDIA_GPU_EXPORT VP9Decoder : public AcceleratedVideoDecoder {
 
     // Submit decode for |pic| to be run in accelerator, taking as arguments
     // information contained in it, as well as current segmentation and loop
-    // filter state in |seg| and |lf|, respectively, and using pictures in
-    // |ref_pictures| for reference.
+    // filter state in |segm_params| and |lf_params|, respectively, and using
+    // pictures in |ref_pictures| for reference.
+    // If done_cb_ is not null, it will be run once decode is done in hardware.
     //
     // Note that returning from this method does not mean that the decode
     // process is finished, but the caller may drop its references to |pic|
-    // and |ref_pictures| immediately, and the data in |seg| and |lf| does not
-    // need to remain valid after this method returns.
+    // and |ref_pictures| immediately, and the data in |segm_params| and
+    // |lf_params| does not need to remain valid after this method returns.
     //
     // Return true when successful, false otherwise.
     virtual bool SubmitDecode(
         const scoped_refptr<VP9Picture>& pic,
-        const Vp9SegmentationParams& seg,
-        const Vp9LoopFilterParams& lf,
-        const std::vector<scoped_refptr<VP9Picture>>& ref_pictures) = 0;
+        const Vp9SegmentationParams& segm_params,
+        const Vp9LoopFilterParams& lf_params,
+        const std::vector<scoped_refptr<VP9Picture>>& ref_pictures,
+        const base::Closure& done_cb) = 0;
 
     // Schedule output (display) of |pic|.
     //
@@ -75,11 +78,21 @@ class MEDIA_GPU_EXPORT VP9Decoder : public AcceleratedVideoDecoder {
     // Return true when successful, false otherwise.
     virtual bool OutputPicture(const scoped_refptr<VP9Picture>& pic) = 0;
 
+    // Return true if the accelerator requires the client to provide frame
+    // context in order to decode. If so, the Vp9FrameHeader provided by the
+    // client must contain a valid compressed header and frame context data.
+    virtual bool IsFrameContextRequired() const = 0;
+
+    // Set |frame_ctx| to the state after decoding |pic|, returning true on
+    // success, false otherwise.
+    virtual bool GetFrameContext(const scoped_refptr<VP9Picture>& pic,
+                                 Vp9FrameContext* frame_ctx) = 0;
+
    private:
     DISALLOW_COPY_AND_ASSIGN(VP9Accelerator);
   };
 
-  VP9Decoder(VP9Accelerator* accelerator);
+  explicit VP9Decoder(VP9Accelerator* accelerator);
   ~VP9Decoder() override;
 
   // AcceleratedVideoDecoder implementation.
@@ -98,6 +111,12 @@ class MEDIA_GPU_EXPORT VP9Decoder : public AcceleratedVideoDecoder {
   // Return true on success, false otherwise.
   bool DecodeAndOutputPicture(scoped_refptr<VP9Picture> pic);
 
+  // Get frame context state after decoding |pic| from the accelerator, and call
+  // |context_refresh_cb| with the acquired state.
+  void UpdateFrameContext(
+      const scoped_refptr<VP9Picture>& pic,
+      const base::Callback<void(const Vp9FrameContext&)>& context_refresh_cb);
+
   // Called on error, when decoding cannot continue. Sets state_ to kError and
   // releases current state.
   void SetError();
@@ -121,11 +140,11 @@ class MEDIA_GPU_EXPORT VP9Decoder : public AcceleratedVideoDecoder {
   // Current coded resolution.
   gfx::Size pic_size_;
 
-  Vp9Parser parser_;
-
   // VP9Accelerator instance owned by the client.
   VP9Accelerator* accelerator_;
 
+  Vp9Parser parser_;
+
   DISALLOW_COPY_AND_ASSIGN(VP9Decoder);
 };