media: Add out-of-line copy ctors for complex classes.

media/capture/video/video_capture_device_info.cc

 // Copyright 2014 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 "media/capture/video/video_capture_device_info.h"
 
 namespace media {
 
 VideoCaptureDeviceInfo::VideoCaptureDeviceInfo() {
 }
 
 VideoCaptureDeviceInfo::VideoCaptureDeviceInfo(
     const VideoCaptureDevice::Name& name,
     const VideoCaptureFormats& supported_formats)
     : name(name), supported_formats(supported_formats) {
 }
 
+VideoCaptureDeviceInfo::VideoCaptureDeviceInfo(
+    const VideoCaptureDeviceInfo& other) = default;
+
 VideoCaptureDeviceInfo::~VideoCaptureDeviceInfo() {
 }
 
 }  // namespace media