Fix Volume slider is captured in screenshot done in touchview mode

chromeos/audio/cras_audio_handler_unittest.cc

Index: chromeos/audio/cras_audio_handler_unittest.cc
diff --git a/chromeos/audio/cras_audio_handler_unittest.cc b/chromeos/audio/cras_audio_handler_unittest.cc
index 7375b4dfa8f0c94e72e3eef31fa6e7789fdfbb4d..b543d6808ec1e18e0bc73313fe4b930949678497 100644
--- a/chromeos/audio/cras_audio_handler_unittest.cc
+++ b/chromeos/audio/cras_audio_handler_unittest.cc
@@ -1976,7 +1976,7 @@ TEST_F(CrasAudioHandlerTest, SetOutputVolumePercent) {
 
   // Verify the output volume is changed to the designated value,
   // OnOutputNodeVolumeChanged event is fired, and the device volume value
-  // is saved the preferences.
+  // is saved in the preferences.
   const int kVolume = 60;
   EXPECT_EQ(kVolume, cras_audio_handler_->GetOutputVolumePercent());
   EXPECT_EQ(1, test_observer_->output_volume_changed_count());
@@ -1986,6 +1986,25 @@ TEST_F(CrasAudioHandlerTest, SetOutputVolumePercent) {
   EXPECT_EQ(kVolume, audio_pref_handler_->GetOutputVolumeValue(&device));
 }
 
+TEST_F(CrasAudioHandlerTest, SetOutputVolumePercentWithoutNotifyingObservers) {
+  AudioNodeList audio_nodes;
+  audio_nodes.push_back(kInternalSpeaker);
+  SetUpCrasAudioHandler(audio_nodes);
+  EXPECT_EQ(0, test_observer_->output_volume_changed_count());
+
+  cras_audio_handler_->SetOutputVolumePercentWithoutNotifyingObservers(60);
+  // Verify the output volume is changed to the designated value,
+  // OnOutputNodeVolumeChanged event is not fired, and the device volume value
+  // is saved in the preferences.
+  const int kVolume = 60;

[Daniel Erat, 2016/07/29 17:53:38]

move this constant up and use it in the SetOutputVolume... call

[Qiang(Joe) Xu, 2016/07/29 18:58:23]

Done.

+  EXPECT_EQ(kVolume, cras_audio_handler_->GetOutputVolumePercent());
+  EXPECT_EQ(0, test_observer_->output_volume_changed_count());
+  AudioDevice device;
+  EXPECT_TRUE(cras_audio_handler_->GetPrimaryActiveOutputDevice(&device));
+  EXPECT_EQ(device.id, kInternalSpeaker.id);
+  EXPECT_EQ(kVolume, audio_pref_handler_->GetOutputVolumeValue(&device));

[Daniel Erat, 2016/07/29 17:53:38]

please also test that further updates _do_ cause notifications now

[Qiang(Joe) Xu, 2016/07/29 18:58:23]

Done.

+}
+
 TEST_F(CrasAudioHandlerTest, SetOutputVolumeWithDelayedSignal) {
   AudioNodeList audio_nodes;
   audio_nodes.push_back(kInternalSpeaker);