Implement HasInputDevices in CrasAudioManager

chromeos/audio/audio_device.h

Index: chromeos/audio/audio_device.h
diff --git a/chromeos/audio/audio_device.h b/chromeos/audio/audio_device.h
index 67dca1cf338a04335be31cd510619681ef4ac0f4..2ed26b1b1316e5284e29c7809401ae0a213784bc 100644
--- a/chromeos/audio/audio_device.h
+++ b/chromeos/audio/audio_device.h
@@ -41,6 +41,20 @@ struct CHROMEOS_EXPORT AudioDevice {
   static std::string GetTypeString(chromeos::AudioDeviceType type);
   static chromeos::AudioDeviceType GetAudioType(const std::string& node_type);
 
+  // Indicates that an input or output audio device is for simple usage like
+  // playback or recording for user. In contrast, audio device such as
+  // loopback, always on keyword recognition (AOKR), and keyboard mic are
+  // not for simple usage.
+  bool is_for_simple_usage() {
+    return (type == AUDIO_TYPE_HEADPHONE ||
+            type == AUDIO_TYPE_INTERNAL_MIC ||
+            type == AUDIO_TYPE_MIC ||
+            type == AUDIO_TYPE_USB ||
+            type == AUDIO_TYPE_BLUETOOTH ||
+            type == AUDIO_TYPE_HDMI ||
+            type == AUDIO_TYPE_INTERNAL_SPEAKER);
+  }
+
   bool is_input;
   uint64 id;
   std::string display_name;