[Mojo Video Capture] Implement a VideoCaptureProvider that uses the video capture service

content/browser/renderer_host/media/mojo_service_video_capture_device_launcher.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 CONTENT_BROWSER_RENDERER_HOST_MEDIA_MOJO_SERVICE_VIDEO_CAPTURE_DEVICE_LAUNCHER_H_
+#define CONTENT_BROWSER_RENDERER_HOST_MEDIA_MOJO_SERVICE_VIDEO_CAPTURE_DEVICE_LAUNCHER_H_
+
+#include "content/browser/renderer_host/media/video_capture_controller.h"
+#include "content/browser/renderer_host/media/video_capture_provider.h"
+#include "content/public/common/media_stream_request.h"
+#include "services/video_capture/public/interfaces/device_factory.mojom.h"
+
+namespace content {
+
+class MojoServiceVideoCaptureDeviceLauncher
+    : public VideoCaptureDeviceLauncher {
+ public:
+  MojoServiceVideoCaptureDeviceLauncher(
+      video_capture::mojom::DeviceFactoryPtr* device_factory);
+  ~MojoServiceVideoCaptureDeviceLauncher() override;
+
+  void LaunchDeviceAsync(const std::string& device_id,
+                         MediaStreamType stream_type,
+                         const media::VideoCaptureParams& params,
+                         base::WeakPtr<media::VideoFrameReceiver> receiver,
+                         Callbacks* callbacks,
+                         base::OnceClosure done_cb) override;
+  void AbortLaunch() override;
+
+  void OnUtilizationReport(int frame_feedback_id, double utilization);
+
+ private:
+  enum class State {
+    READY_TO_LAUNCH,
+    DEVICE_START_IN_PROGRESS,
+    DEVICE_START_ABORTING
+  };
+
+  void OnCreateDeviceCallback(
+      const media::VideoCaptureParams& params,
+      video_capture::mojom::DevicePtr device,
+      base::WeakPtr<media::VideoFrameReceiver> receiver,
+      Callbacks* callbacks,
+      base::OnceClosure done_cb,
+      video_capture::mojom::DeviceAccessResultCode result_code);
+  void OnDeviceCreatedSuccessfully(
+      const media::VideoCaptureParams& params,
+      video_capture::mojom::DevicePtr device,
+      base::WeakPtr<media::VideoFrameReceiver> receiver,
+      Callbacks* callbacks,
+      base::OnceClosure done_cb);
+  void OnDeviceCreationFailed(Callbacks* callbacks, base::OnceClosure done_cb);
+
+  video_capture::mojom::DeviceFactoryPtr* const device_factory_;
+  State state_;
+  base::ThreadChecker thread_checker_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_MOJO_SERVICE_VIDEO_CAPTURE_DEVICE_LAUNCHER_H_