Video Capture Mojo (1.4b): Implement ability to use fake device instance

services/video_capture/fake_device_video_capture_service_unittest.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 "base/memory/ref_counted.h"
+#include "base/run_loop.h"
+#include "services/video_capture/fake_device_video_capture_service_test.h"
+#include "services/video_capture/mock_video_capture_device_client.h"
+#include "services/video_capture/public/interfaces/video_capture_device_factory.mojom.h"
+#include "services/video_capture/video_capture_service_test.h"
+
+using testing::_;
+using testing::InvokeWithoutArgs;
+
+namespace video_capture {
+
+TEST_F(FakeDeviceVideoCaptureServiceTest, FrameCallbacksArrive) {
+  auto arbitrary_requested_format = mojom::VideoCaptureFormat::New();
+  arbitrary_requested_format->frame_size.SetSize(640, 480);
+  arbitrary_requested_format->frame_rate = 15;
+  arbitrary_requested_format->pixel_format = media::mojom::VideoFormat::I420;
+  arbitrary_requested_format->pixel_storage = mojom::VideoPixelStorage::CPU;
+
+  base::RunLoop wait_loop;
+  const int kNumFramesToWaitFor = 3;
+  int num_frames_arrived = 0;
+  mojom::VideoCaptureDeviceClientPtr client_proxy;
+  MockVideoCaptureDeviceClient client(mojo::GetProxy(&client_proxy));
+  EXPECT_CALL(client, OnFrameAvailablePtr(_))
+      .WillRepeatedly(InvokeWithoutArgs(
+          [&wait_loop, &kNumFramesToWaitFor, &num_frames_arrived]() {
+            num_frames_arrived += 1;
+            if (num_frames_arrived >= kNumFramesToWaitFor) {
+              wait_loop.Quit();
+            }
+          }));
+
+  fake_device_proxy_->Start(std::move(arbitrary_requested_format),
+                            mojom::ResolutionChangePolicy::FIXED_RESOLUTION,
+                            mojom::PowerLineFrequency::DEFAULT,
+                            std::move(client_proxy));
+  wait_loop.Run();
+}
+
+}  // namespace video_capture