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

media/capture/video/video_capture_device_info.cc

Index: media/capture/video/video_capture_device_info.cc
diff --git a/media/capture/video/video_capture_device_info.cc b/media/capture/video/video_capture_device_info.cc
index 3bb4df2adac04c4112917253d5f21ea351cd48ff..230c16b381ec62477fd94cf94d80b6989bf3d3b1 100644
--- a/media/capture/video/video_capture_device_info.cc
+++ b/media/capture/video/video_capture_device_info.cc
@@ -15,6 +15,9 @@ VideoCaptureDeviceInfo::VideoCaptureDeviceInfo(
     : name(name), supported_formats(supported_formats) {
 }
 
+VideoCaptureDeviceInfo::VideoCaptureDeviceInfo(
+    const VideoCaptureDeviceInfo& other) = default;
+
 VideoCaptureDeviceInfo::~VideoCaptureDeviceInfo() {
 }