Caching AudioOutputDevice instances in mixer manager

media/base/audio_renderer_mixer_unittest.cc

Index: media/base/audio_renderer_mixer_unittest.cc
diff --git a/media/base/audio_renderer_mixer_unittest.cc b/media/base/audio_renderer_mixer_unittest.cc
index f4c1122e4c380d633a3a57328c5476b51de23b5e..44b95aa0ee1115f12cdd6da1acb5e7053cdf550a 100644
--- a/media/base/audio_renderer_mixer_unittest.cc
+++ b/media/base/audio_renderer_mixer_unittest.cc
@@ -72,7 +72,10 @@ class AudioRendererMixerTest
     EXPECT_CALL(*sink_.get(), Start());
     EXPECT_CALL(*sink_.get(), Stop());
 
-    mixer_.reset(new AudioRendererMixer(output_parameters_, sink_));
+    mixer_.reset(
+        new AudioRendererMixer(output_parameters_, sink_.get(),
+                               base::Bind(&AudioRendererMixerTest::ReleaseSink,
+                                          base::Unretained(this))));
     mixer_callback_ = sink_->callback();
 
     audio_bus_ = AudioBus::Create(output_parameters_);
@@ -96,6 +99,11 @@ class AudioRendererMixerTest
                     const std::string&,
                     const url::Origin&));
 
+  MOCK_METHOD2(GetOutputDeviceInfo,
+               OutputDeviceInfo(const std::string&, const url::Origin&));
+
+  MOCK_METHOD1(ReleaseSink, void(AudioRendererSink*));
+
   void InitializeInputs(int inputs_per_sample_rate) {
     mixer_inputs_.reserve(inputs_per_sample_rate * input_parameters_.size());
     fake_callbacks_.reserve(inputs_per_sample_rate * input_parameters_.size());
@@ -112,13 +120,7 @@ class AudioRendererMixerTest
 
       for (int j = 0; j < inputs_per_sample_rate; ++j, ++input) {
         fake_callbacks_.push_back(new FakeAudioRenderCallback(step));
-        mixer_inputs_.push_back(new AudioRendererMixerInput(
-            base::Bind(&AudioRendererMixerTest::GetMixer,
-                       base::Unretained(this)),
-            base::Bind(&AudioRendererMixerTest::RemoveMixer,
-                       base::Unretained(this)),
-            // Default device ID and security origin.
-            std::string(), url::Origin()));
+        mixer_inputs_.push_back(CreateMixerInput());
         mixer_inputs_[input]->Initialize(input_parameters_[i],
                                          fake_callbacks_[input]);
         mixer_inputs_[input]->SetVolume(1.0f);
@@ -329,6 +331,17 @@ class AudioRendererMixerTest
       mixer_inputs_[i]->Stop();
   }
 
+  scoped_refptr<AudioRendererMixerInput> CreateMixerInput() {
+    return new AudioRendererMixerInput(
+        base::Bind(&AudioRendererMixerTest::GetMixer, base::Unretained(this)),
+        base::Bind(&AudioRendererMixerTest::RemoveMixer,
+                   base::Unretained(this)),
+        base::Bind(&AudioRendererMixerTest::GetOutputDeviceInfo,
+                   base::Unretained(this)),
+        // Default device ID and security origin.
+        std::string(), url::Origin());
+  }
+
  protected:
   virtual ~AudioRendererMixerTest() {}
 
@@ -466,12 +479,7 @@ TEST_P(AudioRendererMixerBehavioralTest, OnRenderErrorPausedInput) {
 TEST_P(AudioRendererMixerBehavioralTest, NoInitialize) {
   EXPECT_CALL(*this, RemoveMixer(testing::_, testing::_, testing::_)).Times(0);
   scoped_refptr<AudioRendererMixerInput> audio_renderer_mixer_input =
-      new AudioRendererMixerInput(
-          base::Bind(&AudioRendererMixerTest::GetMixer, base::Unretained(this)),
-          base::Bind(&AudioRendererMixerTest::RemoveMixer,
-                     base::Unretained(this)),
-          // Default device ID and security origin.
-          std::string(), url::Origin());
+      CreateMixerInput();
 }
 
 // Ensure the physical stream is paused after a certain amount of time with no