Use texture-backed VideoFrane pipeline for Aura desktop capturing.

content/browser/media/capture/desktop_capture_device_aura.cc

Index: content/browser/media/capture/desktop_capture_device_aura.cc
diff --git a/content/browser/media/capture/desktop_capture_device_aura.cc b/content/browser/media/capture/desktop_capture_device_aura.cc
index 2c7d196531b121795f84848105a6603edba4bf54..a4aa46da412ead0e6ec1d2a47bfdbd25eed1ea2a 100644
--- a/content/browser/media/capture/desktop_capture_device_aura.cc
+++ b/content/browser/media/capture/desktop_capture_device_aura.cc
@@ -95,8 +95,8 @@ class DesktopVideoCaptureMachine
   virtual ~DesktopVideoCaptureMachine();
 
   // VideoCaptureFrameSource overrides.
-  virtual bool Start(
-      const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy) OVERRIDE;
+  virtual bool Start(const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy,
+                     const media::VideoCaptureParams& params) OVERRIDE;
   virtual void Stop(const base::Closure& callback) OVERRIDE;
 
   // Implements aura::WindowObserver.
@@ -152,6 +152,9 @@ class DesktopVideoCaptureMachine
   // Makes all the decisions about which frames to copy, and how.
   scoped_refptr<ThreadSafeCaptureOracle> oracle_proxy_;
 
+  // The capture parameters for this capture.
+  media::VideoCaptureParams capture_params_;
+
   // YUV readback pipeline.
   scoped_ptr<content::ReadbackYUVInterface> yuv_readback_pipeline_;
 
@@ -173,7 +176,8 @@ DesktopVideoCaptureMachine::DesktopVideoCaptureMachine(
 DesktopVideoCaptureMachine::~DesktopVideoCaptureMachine() {}
 
 bool DesktopVideoCaptureMachine::Start(
-    const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy) {
+    const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy,
+    const media::VideoCaptureParams& params) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   desktop_window_ = content::DesktopMediaID::GetAuraWindowById(window_id_);
@@ -187,6 +191,7 @@ bool DesktopVideoCaptureMachine::Start(
 
   DCHECK(oracle_proxy.get());
   oracle_proxy_ = oracle_proxy;
+  capture_params_ = params;
 
   // Update capture size.
   UpdateCaptureSize();
@@ -284,7 +289,12 @@ void CopyOutputFinishedForVideo(
   if (!cursor_bitmap.isNull())
     RenderCursorOnVideoFrame(target, cursor_bitmap, cursor_position);
   release_callback->Run(0, false);
-  capture_frame_cb.Run(start_time, result);
+  capture_frame_cb.Run(target, start_time, result);
+}
+
+void RunSingleReleaseCallback(scoped_ptr<cc::SingleReleaseCallback> cb,
+                              scoped_ptr<gpu::MailboxHolder> mailbox_holder) {
+  cb->Run(mailbox_holder->sync_point, false);
 }
 
 void DesktopVideoCaptureMachine::DidCopyOutput(
@@ -295,6 +305,29 @@ void DesktopVideoCaptureMachine::DidCopyOutput(
   if (result->IsEmpty() || result->size().IsEmpty() || !desktop_layer_)
     return;
 
+  if (capture_params_.requested_format.pixel_format ==
+      media::PIXEL_FORMAT_TEXTURE) {
+    DCHECK(!video_frame);
+    cc::TextureMailbox texture_mailbox;
+    scoped_ptr<cc::SingleReleaseCallback> release_callback;
+    result->TakeTexture(&texture_mailbox, &release_callback);
+    DCHECK(texture_mailbox.IsTexture());
+    if (!texture_mailbox.IsTexture())
+      return;
+    video_frame = media::VideoFrame::WrapNativeTexture(
+        make_scoped_ptr(new gpu::MailboxHolder(texture_mailbox.mailbox(),
+                                               texture_mailbox.target(),
+                                               texture_mailbox.sync_point())),
+        base::Bind(&RunSingleReleaseCallback, base::Passed(&release_callback)),
+        result->size(),
+        gfx::Rect(result->size()),
+        result->size(),
+        base::TimeDelta(),

[Ami GONE FROM CHROMIUM, 2014/04/01 18:03:38]

Why the empty TimeDelta?

[sheu, 2014/04/21 20:39:39]

Just stubbed for now.  It would be better to have some sort of timestamp
reported back from the CopyOutputRequest.

+        media::VideoFrame::ReadPixelsCB());

[Ami GONE FROM CHROMIUM, 2014/04/01 18:03:38]

Why the empty ReadPixelsCB?

[sheu, 2014/04/21 20:39:39]

Not expecting this frame to be read back to software buffers, for now.

+    capture_frame_cb.Run(video_frame, start_time, true);
+    return;

[sheu, 2014/04/01 00:11:26]

Cursor compositing doesn't happen, of course.

+  }
+
   // Compute the dest size we want after the letterboxing resize. Make the
   // coordinates and sizes even because we letterbox in YUV space
   // (see CopyRGBToVideoFrame). They need to be even for the UV samples to
@@ -439,7 +472,11 @@ void DesktopCaptureDeviceAura::AllocateAndStart(
     const media::VideoCaptureParams& params,
     scoped_ptr<Client> client) {
   DVLOG(1) << "Allocating " << params.requested_format.frame_size.ToString();
-  core_->AllocateAndStart(params, client.Pass());
+  media::VideoCaptureParams new_params = params;
+  // Desktop capture devices ignore the requested size and return the actual
+  // captured desktop size.
+  new_params.requested_format.frame_size.SetSize(0, 0);
+  core_->AllocateAndStart(new_params, client.Pass());
 }
 
 void DesktopCaptureDeviceAura::StopAndDeAllocate() {