[Mojo Video Capture] Adapt video_capture service to refactored video capture stack

services/video_capture/device_media_to_mojo_adapter.cc

Index: services/video_capture/device_media_to_mojo_adapter.cc
diff --git a/services/video_capture/device_media_to_mojo_adapter.cc b/services/video_capture/device_media_to_mojo_adapter.cc
index a68c87fbb6b1e19c1fd14cebd438103079f7631b..ea7656a2efa153af72827e4d57c8035cc10fcfd5 100644
--- a/services/video_capture/device_media_to_mojo_adapter.cc
+++ b/services/video_capture/device_media_to_mojo_adapter.cc
@@ -11,6 +11,14 @@
 #include "media/capture/video/video_capture_jpeg_decoder.h"
 #include "services/video_capture/receiver_mojo_to_media_adapter.h"
 
+namespace {
+
+// The maximum number of video frame buffers in-flight at any one time.
+// If all buffers are still in use by consumers when new frames are produced
+// those frames get dropped.
+static const int kMaxBufferCount = 3;
+}
+
 namespace video_capture {
 
 DeviceMediaToMojoAdapter::DeviceMediaToMojoAdapter(
@@ -22,7 +30,8 @@ DeviceMediaToMojoAdapter::DeviceMediaToMojoAdapter(
       device_running_(false) {}
 
 DeviceMediaToMojoAdapter::~DeviceMediaToMojoAdapter() {
-  Stop();
+  if (device_running_)
+    device_->StopAndDeAllocate();
 }
 
 void DeviceMediaToMojoAdapter::Start(
@@ -36,12 +45,11 @@ void DeviceMediaToMojoAdapter::Start(
       base::MakeUnique<ReceiverMojoToMediaAdapter>(std::move(receiver));
 
   // Create a dedicated buffer pool for the device usage session.
-  const int kMaxBufferCount = 2;
   auto buffer_tracker_factory =
       base::MakeUnique<media::VideoCaptureBufferTrackerFactoryImpl>();
   scoped_refptr<media::VideoCaptureBufferPool> buffer_pool(
       new media::VideoCaptureBufferPoolImpl(std::move(buffer_tracker_factory),
-                                            kMaxBufferCount));
+                                            max_buffer_pool_buffer_count()));
 
   auto device_client = base::MakeUnique<media::VideoCaptureDeviceClient>(
       std::move(media_receiver), buffer_pool, jpeg_decoder_factory_callback_);
@@ -50,15 +58,26 @@ void DeviceMediaToMojoAdapter::Start(
   device_running_ = true;
 }
 
+void DeviceMediaToMojoAdapter::OnReceiverReportingUtilization(
+    int32_t frame_feedback_id,
+    double utilization) {
+  device_->OnUtilizationReport(frame_feedback_id, utilization);
+}
+
 void DeviceMediaToMojoAdapter::Stop() {
   if (device_running_ == false)
     return;
-  device_->StopAndDeAllocate();
   device_running_ = false;
+  device_->StopAndDeAllocate();
 }
 
 void DeviceMediaToMojoAdapter::OnClientConnectionErrorOrClose() {
   Stop();
 }
 
+// static
+int DeviceMediaToMojoAdapter::max_buffer_pool_buffer_count() {
+  return kMaxBufferCount;
+}
+
 }  // namespace video_capture