Pass big metadata parameter by reference

Reduce copies of PipelineMetada (which contains AudioDecoderConfig
and VideoDecoderConfig) by using pass by reference.

This was originally authored by Andre Rosa<andre.rosa@lge.com>

Change-Id: I9ddf137d5d35154862501edcbbfe5b26c1dacbf0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1601613
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: John Rummell <jrummell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#658829}

media/base/mock_filters.h

@@ -52,7 +52,7 @@ class MockPipelineClient : public Pipeline::Client {
 
   MOCK_METHOD1(OnError, void(PipelineStatus));
   MOCK_METHOD0(OnEnded, void());
-  MOCK_METHOD1(OnMetadata, void(PipelineMetadata));
+  MOCK_METHOD1(OnMetadata, void(const PipelineMetadata&));
   MOCK_METHOD1(OnBufferingStateChange, void(BufferingState));
   MOCK_METHOD0(OnDurationChange, void());
   MOCK_METHOD2(OnAddTextTrack,

media/base/pipeline.h

@@ -45,7 +45,7 @@ class MEDIA_EXPORT Pipeline {
     // Executed when the content duration, container video size, start time,
     // and whether the content has audio and/or video in supported formats are
     // known.
-    virtual void OnMetadata(PipelineMetadata metadata) = 0;
+    virtual void OnMetadata(const PipelineMetadata& metadata) = 0;
 
     // Executed whenever there are changes in the buffering state of the
     // pipeline.

media/base/pipeline_impl.cc

@@ -1301,7 +1301,7 @@ void PipelineImpl::OnEnded() {
   client_->OnEnded();
 }
 
-void PipelineImpl::OnMetadata(PipelineMetadata metadata) {
+void PipelineImpl::OnMetadata(const PipelineMetadata& metadata) {
   DVLOG(2) << __func__;
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(IsRunning());

media/base/pipeline_impl.h

@@ -135,7 +135,7 @@ class MEDIA_EXPORT PipelineImpl : public Pipeline {
   // Notifications from RendererWrapper.
   void OnError(PipelineStatus error);
   void OnEnded();
-  void OnMetadata(PipelineMetadata metadata);
+  void OnMetadata(const PipelineMetadata& metadata);
   void OnBufferingStateChange(BufferingState state);
   void OnDurationChange(base::TimeDelta duration);
   void OnWaiting(WaitingReason reason);

media/blink/webmediaplayer_impl.cc

@@ -1755,7 +1755,7 @@ void WebMediaPlayerImpl::OnEnded() {
   UpdatePlayState();
 }
 
-void WebMediaPlayerImpl::OnMetadata(PipelineMetadata metadata) {
+void WebMediaPlayerImpl::OnMetadata(const PipelineMetadata& metadata) {
   DVLOG(1) << __func__;
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 

media/blink/webmediaplayer_impl.h

@@ -322,7 +322,7 @@ class MEDIA_BLINK_EXPORT WebMediaPlayerImpl
   // Pipeline::Client overrides.
   void OnError(PipelineStatus status) override;
   void OnEnded() override;
-  void OnMetadata(PipelineMetadata metadata) override;
+  void OnMetadata(const PipelineMetadata& metadata) override;
   void OnBufferingStateChange(BufferingState state) override;
   void OnDurationChange() override;
   void OnAddTextTrack(const TextTrackConfig& config,

media/blink/webmediaplayer_impl_unittest.cc

@@ -456,7 +456,9 @@ class WebMediaPlayerImplTest : public testing::Test {
     wmpi_->OnError(status);
   }
 
-  void OnMetadata(PipelineMetadata metadata) { wmpi_->OnMetadata(metadata); }
+  void OnMetadata(const PipelineMetadata& metadata) {
+    wmpi_->OnMetadata(metadata);
+  }
 
   void OnWaiting(WaitingReason reason) { wmpi_->OnWaiting(reason); }
 

media/filters/pipeline_controller_unittest.cc

@@ -142,7 +142,7 @@ class PipelineControllerTest : public ::testing::Test, public Pipeline::Client {
   // Pipeline::Client overrides
   void OnError(PipelineStatus status) override { NOTREACHED(); }
   void OnEnded() override {}
-  void OnMetadata(PipelineMetadata metadata) override {}
+  void OnMetadata(const PipelineMetadata& metadata) override {}
   void OnBufferingStateChange(BufferingState state) override {}
   void OnDurationChange() override {}
   void OnAddTextTrack(const TextTrackConfig& config,

media/test/pipeline_integration_test_base.h

@@ -229,7 +229,7 @@ class PipelineIntegrationTestBase : public Pipeline::Client {
   // Pipeline::Client overrides.
   void OnError(PipelineStatus status) override;
   void OnEnded() override;
-  MOCK_METHOD1(OnMetadata, void(PipelineMetadata));
+  MOCK_METHOD1(OnMetadata, void(const PipelineMetadata&));
   MOCK_METHOD1(OnBufferingStateChange, void(BufferingState));
   MOCK_METHOD0(OnDurationChange, void());
   MOCK_METHOD2(OnAddTextTrack,