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

chromeos/audio/audio_devices_pref_handler_impl_unittest.cc

 // Copyright 2014 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/audio_devices_pref_handler_impl.h"
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "chromeos/audio/audio_device.h"
 #include "chromeos/audio/audio_devices_pref_handler.h"
 #include "chromeos/chromeos_pref_names.h"
 #include "chromeos/dbus/audio_node.h"
 #include "components/prefs/testing_pref_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace chromeos {
 
 const uint64_t kInternalMicId = 10003;
 const uint64_t kHeadphoneId = 10002;
 const uint64_t kHDMIOutputId = 10006;
+const uint64_t kUSBMicId = 10004;
 const uint64_t kOtherTypeOutputId = 90001;
 const uint64_t kOtherTypeInputId = 90002;
 
 const AudioDevice kInternalMic(AudioNode(true,
                                          kInternalMicId,
                                          kInternalMicId,
                                          "Fake Mic",
                                          "INTERNAL_MIC",
                                          "Internal Mic",
                                          false,
                                          0));
+const AudioDevice kUSBMic(AudioNode(true,
+                                    kUSBMicId,
+                                    kUSBMicId,
+                                    "Fake USB Mic",
+                                    "USB",
+                                    "USB Microphone",
+                                    false,
+                                    0));
 
 const AudioDevice kHeadphone(AudioNode(false,
                                        kHeadphoneId,
                                        kHeadphoneId,
                                        "Fake Headphone",
                                        "HEADPHONE",
                                        "Headphone",
                                        false,
                                        0));
 
@@ skipping 103 matching lines @@
   audio_pref_handler_->SetDeviceActive(kHeadphone, true, false);
   EXPECT_TRUE(audio_pref_handler_->GetDeviceActive(kHeadphone, &active,
                                                    &activate_by_user));
   EXPECT_TRUE(active);
   EXPECT_FALSE(activate_by_user);
 
   audio_pref_handler_->SetDeviceActive(kHDMIOutput, false, false);
   EXPECT_TRUE(audio_pref_handler_->GetDeviceActive(kHDMIOutput, &active,
                                                    &activate_by_user));
   EXPECT_FALSE(active);
+
+  // Device not exist in device state prefs.
+  EXPECT_FALSE(audio_pref_handler_->GetDeviceActive(kUSBMic, &active,
+                                                    &activate_by_user));
 }
 
 }  // namespace chromeos