Let clients interact with VideoCaptureDeviceClient instead of VideoCaptureDevice

services/video_capture/mojo_shared_memory_buffer_tracker.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "services/video_capture/mojo_shared_memory_buffer_tracker.h"
+
+#include "base/memory/ptr_util.h"
+#include "services/video_capture/mojo_shared_memory_buffer_handle.h"
+
+namespace video_capture {
+
+MojoSharedMemoryBufferTracker::MojoSharedMemoryBufferTracker()
+    : VideoCaptureBufferTracker() {}
+
+MojoSharedMemoryBufferTracker::~MojoSharedMemoryBufferTracker() = default;
+
+bool MojoSharedMemoryBufferTracker::Init(const gfx::Size& dimensions,
+                                         media::VideoPixelFormat format,
+                                         media::VideoPixelStorage storage_type,
+                                         base::Lock* lock) {
+  if ((format != media::PIXEL_FORMAT_I420) ||
+      (storage_type != media::PIXEL_STORAGE_CPU)) {
+    LOG(ERROR) << "Unsupported pixel format or storage type";
+    return false;
+  }
+
+  set_dimensions(dimensions);
+  set_max_pixel_count(dimensions.GetArea());
+  set_pixel_format(format);
+  set_storage_type(storage_type);
+  mapped_size_ =
+      media::VideoCaptureFormat(dimensions, 0.0f, format, storage_type)
+          .ImageAllocationSize();
+
+  frame_ = media::MojoSharedBufferVideoFrame::CreateDefaultI420(
+      dimensions, base::TimeDelta());

[emircan, 2016/10/10 18:46:13]

As I explained offline, sending these buffers might result in an extra copy
compared to the current case when using HW encoders. In order to share the
buffers from renderer to gpu process, we need a shmem handle as it is still via
IPC. MojoSharedBufferVideoFrame will be copied in RTCVideoEncoder currently.

https://cs.chromium.org/chromium/src/content/renderer/media/gpu/rtc_video_enc...
https://cs.chromium.org/chromium/src/media/gpu/ipc/client/gpu_video_encode_ac...

[chfremer, 2016/10/11 19:09:07]

Thanks. I have added a task to the design doc for dealing with this.

+  return true;
+}
+
+std::unique_ptr<media::VideoCaptureBufferHandle>
+MojoSharedMemoryBufferTracker::GetBufferHandle() {
+  return base::MakeUnique<MojoSharedMemoryBufferHandle>(this);
+}
+
+bool MojoSharedMemoryBufferTracker::ShareToProcess(
+    base::ProcessHandle process_handle,
+    base::SharedMemoryHandle* new_handle) {
+  return false;
+}
+
+bool MojoSharedMemoryBufferTracker::ShareToProcess2(
+    int plane,
+    base::ProcessHandle process_handle,
+    gfx::GpuMemoryBufferHandle* new_handle) {
+  return false;
+}
+
+}  // namespace video_capture