Add constructors and operators to MediaDeviceInfo.

content/common/media/media_devices_unittest.cc

+// Copyright 2015 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 "content/common/media/media_devices.h"
+#include "media/audio/audio_device_description.h"
+#include "media/capture/video/video_capture_device_descriptor.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+
+TEST(MediaDevicesTest, MediaDeviceInfoFromAudioDescription) {
+  const std::string kFakeDeviceID = "fake_device_id";
+  const std::string kFakeLabel = "fake_label";
+  const std::string kFakeGroupID = "fake_group_id";
+
+  media::AudioDeviceDescription description(kFakeLabel, kFakeDeviceID,
+                                            kFakeGroupID);
+  MediaDeviceInfo device_info(description);
+  EXPECT_EQ(kFakeDeviceID, device_info.device_id);
+  EXPECT_EQ(kFakeLabel, device_info.label);
+  EXPECT_EQ(kFakeGroupID, device_info.group_id);
+}
+
+TEST(MediaDevicesTest, MediaDeviceInfoFromVideoDescriptor) {
+  media::VideoCaptureDeviceDescriptor descriptor(
+      "display_name", "device_id", "model_id", media::VideoCaptureApi::UNKNOWN);
+
+  // TODO(guidou): Add test for group ID when supported. See crbug.com/627793.
+  MediaDeviceInfo device_info(descriptor);
+  EXPECT_EQ(descriptor.device_id, device_info.device_id);
+  EXPECT_EQ(descriptor.GetNameAndModel(), device_info.label);
+}
+
+}  // namespace content