Fix the corner case for new audio device is not selected as active if it is plugged in for the firs…

chromeos/audio/cras_audio_handler_unittest.cc

 // Copyright (c) 2013 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.
 
 #include "chromeos/audio/cras_audio_handler.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 2354 matching lines @@
   audio_nodes.push_back(kHeadphone);
   ChangeAudioNodes(audio_nodes);
 
   // Verify the active output has been restored to internal speaker.
   cras_audio_handler_->GetAudioDevices(&audio_devices);
   EXPECT_EQ(audio_nodes.size(), audio_devices.size());
   EXPECT_EQ(kInternalSpeaker.id,
             cras_audio_handler_->GetPrimaryActiveOutputNode());
 }
 
+// Test the corner case that headphone is plugged in for the first time on
+// a cros device after the device is shutdown.
+// crbug.com/622045.
+TEST_F(CrasAudioHandlerTest, PlugInHeadphoneFirstTimeAfterPowerDown) {
+  // Simulate plugging headphone for the first on a cros device after it is
+  // powered down. Internal speaker is set up in audio prefs as active
+  // before the new cros session starts.
+  AudioNodeList audio_nodes_in_pref;
+  audio_nodes_in_pref.push_back(kInternalSpeaker);
+
+  AudioNodeList audio_nodes;
+  audio_nodes.push_back(kInternalSpeaker);
+  audio_nodes.push_back(kHeadphone);
+
+  SetupCrasAudioHandlerWithActiveNodeInPref(
+      audio_nodes, audio_nodes_in_pref, AudioDevice(kInternalSpeaker), false);
+
+  // Verify the audio devices size.
+  AudioDeviceList audio_devices;
+  cras_audio_handler_->GetAudioDevices(&audio_devices);
+  EXPECT_EQ(audio_nodes.size(), audio_devices.size());
+
+  // Verify headphone becomes the active output.
+  EXPECT_EQ(kHeadphone.id, cras_audio_handler_->GetPrimaryActiveOutputNode());
+}
+
 TEST_F(CrasAudioHandlerTest,
        PersistActiveUsbHeadphoneAcrossRebootUsbComeLater) {
   // Simulates the device was shut down with three audio devices, and
   // usb headphone being the active one selected by priority.
   AudioNodeList audio_nodes_in_pref;
   audio_nodes_in_pref.push_back(kInternalSpeaker);
   audio_nodes_in_pref.push_back(kHeadphone);
   audio_nodes_in_pref.push_back(kUSBHeadphone1);
 
   // Simulate the first NodesChanged signal coming with only internal speaker
@@ skipping 882 matching lines @@
       cras_audio_handler_->GetPrimaryActiveOutputDevice(&active_output));
   EXPECT_EQ(kInternalSpeaker.id, active_output.id);
   EXPECT_EQ(kInternalSpeaker.id,
             cras_audio_handler_->GetPrimaryActiveOutputNode());
   EXPECT_FALSE(cras_audio_handler_->IsOutputMuted());
   EXPECT_EQ(1, test_observer_->output_mute_changed_count());
   EXPECT_TRUE(test_observer_->output_mute_by_system());
 }
 
 }  // namespace chromeos