Switch base::Value typemapping to be by value instead of by unique_ptr.

content/renderer/media/video_capture_impl.cc

 // Copyright (c) 2012 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.
 //
 // Notes about usage of this object by VideoCaptureImplManager.
 //
 // VideoCaptureImplManager access this object by using a Unretained()
 // binding and tasks on the IO thread. It is then important that
 // VideoCaptureImpl never post task to itself. All operations must be
 // synchronous.
@@ skipping 266 matching lines @@
                 << VideoPixelFormatToString(info->pixel_format)
                 << ", storage:" << info->storage_type;
   }
   if (!consume_buffer) {
     GetVideoCaptureHost()->ReleaseBuffer(device_id_, buffer_id, -1.0);
     return;
   }
 
   base::TimeTicks reference_time;
   media::VideoFrameMetadata frame_metadata;
-  frame_metadata.MergeInternalValuesFrom(*info->metadata);
+  frame_metadata.MergeInternalValuesFrom(info->metadata);
   const bool success = frame_metadata.GetTimeTicks(
       media::VideoFrameMetadata::REFERENCE_TIME, &reference_time);
   DCHECK(success);
 
   if (first_frame_ref_time_.is_null())
     first_frame_ref_time_ = reference_time;
 
   // If the timestamp is not prepared, we use reference time to make a rough
   // estimate. e.g. ThreadSafeCaptureOracle::DidCaptureFrame().
   // TODO(miu): Fix upstream capturers to always set timestamp and reference
@@ skipping 24 matching lines @@
     return;
   }
 
   BufferFinishedCallback buffer_finished_callback = media::BindToCurrentLoop(
       base::Bind(&VideoCaptureImpl::OnClientBufferFinished,
                  weak_factory_.GetWeakPtr(), buffer_id, buffer));
   frame->AddDestructionObserver(
       base::Bind(&VideoCaptureImpl::DidFinishConsumingFrame, frame->metadata(),
                  buffer_finished_callback));
 
-  frame->metadata()->MergeInternalValuesFrom(*info->metadata);
+  frame->metadata()->MergeInternalValuesFrom(info->metadata);
 
   // TODO(qiangchen): Dive into the full code path to let frame metadata hold
   // reference time rather than using an extra parameter.
   for (const auto& client : clients_)
     client.second.deliver_frame_cb.Run(frame, reference_time);
 }
 
 void VideoCaptureImpl::OnBufferDestroyed(int32_t buffer_id) {
   DCHECK(io_thread_checker_.CalledOnValidThread());
 
@@ skipping 96 matching lines @@
   // destructor.  |metadata| is still valid for read-access at this point.
   double consumer_resource_utilization = -1.0;
   if (!metadata->GetDouble(media::VideoFrameMetadata::RESOURCE_UTILIZATION,
                            &consumer_resource_utilization)) {
     consumer_resource_utilization = -1.0;
   }
   callback_to_io_thread.Run(consumer_resource_utilization);
 }
 
 }  // namespace content