[Mojo Video Capture] Use string keys instead of VideoCaptureDeviceDescriptor

services/video_capture/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/public/interfaces/video_capture_device_factory.mojom.h"
 #include "services/video_capture/video_capture_service_test.h"
 
 using testing::Exactly;
@@ skipping 36 matching lines @@
   factory_->EnumerateDeviceDescriptors(base::Bind(
       &MockDeviceDescriptorReceiver::OnEnumerateDeviceDescriptorsCallback,
       base::Unretained(&descriptor_receiver_)));
   wait_loop.Run();
   ASSERT_EQ(1u, num_devices_enumerated);
 }
 
 // Tests that VideoCaptureDeviceFactory::CreateDeviceProxy() returns an error
 // code when trying to create a device for an invalid descriptor.
 TEST_F(VideoCaptureServiceTest, ErrorCodeOnCreateDeviceForInvalidDescriptor) {
-  media::VideoCaptureDeviceDescriptor invalid_descriptor;
-  invalid_descriptor.device_id = "invalid";
-  invalid_descriptor.model_id = "invalid";
+  const std::string invalid_device_id = "invalid";
   base::RunLoop wait_loop;
   mojom::VideoCaptureDeviceProxyPtr fake_device_proxy;
   MockCreateDeviceProxyCallback create_device_proxy_callback;
   EXPECT_CALL(create_device_proxy_callback,
               Run(mojom::DeviceAccessResultCode::ERROR_DEVICE_NOT_FOUND))
       .Times(1)
       .WillOnce(InvokeWithoutArgs([&wait_loop]() { wait_loop.Quit(); }));
   factory_->CreateDeviceProxy(
-      std::move(invalid_descriptor), mojo::GetProxy(&fake_device_proxy),
+      invalid_device_id, mojo::GetProxy(&fake_device_proxy),
       base::Bind(&MockCreateDeviceProxyCallback::Run,
                  base::Unretained(&create_device_proxy_callback)));
   wait_loop.Run();
 }
 
 }  // namespace video_capture