media: add video capture device for ARC++ camera HAL v3

media/capture/video/chromeos/video_capture_device_factory_chromeos.h

+// Copyright 2017 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.
+
+#ifndef MEDIA_CAPTURE_VIDEO_CHROMEOS_VIDEO_CAPTURE_DEVICE_FACTORY_CHROMEOS_H_
+#define MEDIA_CAPTURE_VIDEO_CHROMEOS_VIDEO_CAPTURE_DEVICE_FACTORY_CHROMEOS_H_
+
+#include <memory>
+
+#include "base/macros.h"
+#include "media/capture/video/chromeos/camera_hal_delegate.h"
+#include "media/capture/video/video_capture_device_factory.h"
+
+namespace media {
+
+class CAPTURE_EXPORT VideoCaptureDeviceFactoryChromeOS final
+    : public VideoCaptureDeviceFactory {
+ public:
+  explicit VideoCaptureDeviceFactoryChromeOS(
+      scoped_refptr<base::SingleThreadTaskRunner>
+          task_runner_for_screen_observer);
+
+  ~VideoCaptureDeviceFactoryChromeOS() override;
+
+  // VideoCaptureDeviceFactory interface implementations.
+  std::unique_ptr<VideoCaptureDevice> CreateDevice(
+      const VideoCaptureDeviceDescriptor& device_descriptor) final;
+  void GetSupportedFormats(
+      const VideoCaptureDeviceDescriptor& device_descriptor,
+      VideoCaptureFormats* supported_formats) final;
+  void GetDeviceDescriptors(
+      VideoCaptureDeviceDescriptors* device_descriptors) final;
+
+  // Initializes the factory. The factory is functional only after this call
+  // succeeds.
+  bool Init();
+
+  // A run-time check for whether we should enable
+  // VideoCaptureDeviceFactoryChromeOS on the device.
+  static bool ShouldEnable();
+
+ private:
+  const scoped_refptr<base::SingleThreadTaskRunner>
+      task_runner_for_screen_observer_;
+
+  // The thread that all the Mojo operations of |camera_hal_delegate_| take
+  // place.  Started in Init and stopped when the class instance is destroyed.
+  base::Thread camera_hal_ipc_thread_;
+
+  // Communication interface to the camera HAL.  |camera_hal_delegate_| is
+  // created on the thread on which Init is called.  All the Mojo communication
+  // that |camera_hal_delegate_| issues and receives must be sequenced through
+  // |camera_hal_ipc_thread_|.
+  scoped_refptr<CameraHalDelegate> camera_hal_delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceFactoryChromeOS);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CAPTURE_VIDEO_CHROMEOS_VIDEO_CAPTURE_DEVICE_FACTORY_CHROMEOS_H_