Pass GpuMemoryBuffer backed VideoFrame from browser to renderer processes

This is a CL for Video Capture using GpuMemoryBuffers plan[0]. The plans for future CLs can be seen on [1].

[0] https://docs.google.com/document/d/1lobWf168_Kq05TLNLX81gRQwY5oe4k2t3oP-XTBEpIo/edit#heading=h.lflt7hoq3oui
[1] https://docs.google.com/document/d/1lobWf168_Kq05TLNLX81gRQwY5oe4k2t3oP-XTBEpIo/edit#heading=h.exy0h9917c1d

- Changed VideoCaptureBufferPool::ShareToProcess() method to handle sharing both SharedMemory and GpuMemoryBuffer backed video frames.
- Added VideoCaptureBufferPool::GpuMemoryBufferTracker::ShareToProcess() for sharing GMB backed buffers.
- Added dimensions() method to media::VideoCaptureDevice::Client::Buffer and VideoCaptureBufferPool::BufferHandle interfaces as required by GMB mapping. Also, renamed size() to mapped_size() to avoid confusion.
- Added OnGpuMemoryBufferCreated() calls between Browser and Renderer to notify the creation of GMB backed buffers and pass handles.
- Added VideoCaptureImpl::ClientGpuMemoryBuffer on Renderer side to create&map new GMB client buffers.

Also, buffer reuse and destruction is handled behind VideoCaptureDeviceClient::AutoReleaseBuffer like listed below:

Buffer Creation
*Browser
VideoCaptureController::DoIncomingCapturedVideoFrameOnIOThread
- ShareToProcess(Renderer)
VideoCaptureHost::OnBufferCreated
*Renderer
VideoCaptureMessageFilter::OnBufferCreated
VideoCaptureImpl::OnBufferCreated
- Adds to client_buffers_

Buffer Reuse
*Renderer
VideoCaptureImpl::OnClientBufferFinished
*Browser
VideoCaptureHost::OnRendererFinishedWithBuffer
VideoCaptureController::ReturnBuffer
VideoCaptureBufferPool::RelinquishConsumerHold
~AutoReleaseBuffer
VideoCaptureBufferPool::RelinquishProducerReservation

BUG=440843, 503835
TEST=
- Without the kUseGpuMemoryBuffersForCapture flag, AppRTC loopback runs as before.
- With the flag, AppRTC loopback crashes in VideoCaptureHost::OnBufferReady as expected.

Review URL: https://codereview.chromium.org/1267883002

Cr-Commit-Position: refs/heads/master@{#346414}

4 files changed, 11 insertions, 7 deletions

diff --git a/media/capture/content/thread_safe_capture_oracle.cc b/media/capture/content/thread_safe_capture_oracle.cc
index cbc4948..5bedc4a 100644
--- a/media/capture/content/thread_safe_capture_oracle.cc
+++ b/media/capture/content/thread_safe_capture_oracle.cc
@@ -119,7 +119,7 @@ bool ThreadSafeCaptureOracle::ObserveEventAndDecideCapture(
     *storage = VideoFrame::WrapExternalData(
         media::PIXEL_FORMAT_I420, coded_size, gfx::Rect(visible_size),
         visible_size, static_cast<uint8*>(output_buffer->data()),
-        output_buffer->size(), base::TimeDelta());
+        output_buffer->mapped_size(), base::TimeDelta());
     DCHECK(*storage);
   }
   *callback =
diff --git a/media/capture/video/fake_video_capture_device.cc b/media/capture/video/fake_video_capture_device.cc
index 70c7eb4..59f6625 100644
--- a/media/capture/video/fake_video_capture_device.cc
+++ b/media/capture/video/fake_video_capture_device.cc
@@ -198,7 +198,7 @@ void FakeVideoCaptureDevice::CaptureUsingClientBuffers(
     DCHECK_EQ(capture_format_.pixel_storage, PIXEL_STORAGE_CPU);
     DCHECK_EQ(capture_format_.pixel_format, VIDEO_CAPTURE_PIXEL_FORMAT_ARGB);
     uint8_t* data_ptr = static_cast<uint8_t*>(capture_buffer->data());
-    memset(data_ptr, 0, capture_buffer->size());
+    memset(data_ptr, 0, capture_buffer->mapped_size());
     DrawPacman(true /* use_argb */, data_ptr, frame_count_,
                kFakeCapturePeriodMs, capture_format_.frame_size);
   }
diff --git a/media/capture/video/fake_video_capture_device_unittest.cc b/media/capture/video/fake_video_capture_device_unittest.cc
index 9b92462..c73f5888 100644
--- a/media/capture/video/fake_video_capture_device_unittest.cc
+++ b/media/capture/video/fake_video_capture_device_unittest.cc
@@ -27,12 +27,15 @@ namespace {
 // This class is a Client::Buffer that allocates and frees the requested |size|.
 class MockBuffer : public VideoCaptureDevice::Client::Buffer {
  public:
-  MockBuffer(int buffer_id, size_t size)
-      : id_(buffer_id), size_(size), data_(new uint8[size_]) {}
+  MockBuffer(int buffer_id, size_t mapped_size)
+      : id_(buffer_id),
+        mapped_size_(mapped_size),
+        data_(new uint8[mapped_size]) {}
   ~MockBuffer() override { delete[] data_; }
 
   int id() const override { return id_; }
-  size_t size() const override { return size_; }
+  gfx::Size dimensions() const override { return gfx::Size(); }
+  size_t mapped_size() const override { return mapped_size_; }
   void* data(int plane) override { return data_; }
   ClientBuffer AsClientBuffer(int plane) override { return nullptr; }
 #if defined(OS_POSIX)
@@ -43,7 +46,7 @@ class MockBuffer : public VideoCaptureDevice::Client::Buffer {
 
  private:
   const int id_;
-  const size_t size_;
+  const size_t mapped_size_;
   uint8* const data_;
 };
 
diff --git a/media/capture/video/video_capture_device.h b/media/capture/video/video_capture_device.h
index ea219ff..eabefab 100644
--- a/media/capture/video/video_capture_device.h
+++ b/media/capture/video/video_capture_device.h
@@ -181,7 +181,8 @@ class MEDIA_EXPORT VideoCaptureDevice {
      public:
       virtual ~Buffer() = 0;
       virtual int id() const = 0;
-      virtual size_t size() const = 0;
+      virtual gfx::Size dimensions() const = 0;
+      virtual size_t mapped_size() const = 0;
       virtual void* data(int plane) = 0;
       void* data() { return data(0); }
       virtual ClientBuffer AsClientBuffer(int plane) = 0;