Add Audio Volume Control Type

Test: cast_receiver_unittests
      cast_service_unittests

Test(new): MdnsCastService.ChangeFixedVolumeDevice
	   MdnsCastService.ChangeMasterVolumeDevice,
	   MediaManagerImpl.UpdateDeviceVolumeType,

Bug: 22685803

Change-Id: I73b3339493451b5f38adef598359cc01c3451b37

Review URL: https://codereview.chromium.org/1532823002

Cr-Commit-Position: refs/heads/master@{#366229}

1 files changed, 28 insertions, 6 deletions

diff --git a/chromecast/public/avsettings.h b/chromecast/public/avsettings.h
index 87c4a15..9f9688a 100644
--- a/chromecast/public/avsettings.h
+++ b/chromecast/public/avsettings.h
@@ -35,6 +35,23 @@ class AvSettings {
     LPCM = 1 << 4,
   };
 
+  // Defines the type of audio volume control of the device.
+  enum AudioVolumeControlType {
+    UNKNOWN_VOLUME,
+
+    // MASTER_VOLUME: Devices of CEC audio controls is a master volume system,
+    // i.e the system volume is changed, but not attenuated,
+    // e.g. normal TVs, audio devices.
+    MASTER_VOLUME,
+
+    // ATTENUATION_VOLUME: Devices which do not do CEC audio controls,
+    // e.g. Chromecast.
+    ATTENUATION_VOLUME,
+
+    // FIXED_VOLUME: Devices which have fixed volume, e.g. Nexus Player.
+    FIXED_VOLUME,
+  };
+
   enum Event {
     // This event shall be fired whenever the active state is changed including
     // when the screen turned on, when the cast receiver (or the device where
@@ -70,6 +87,11 @@ class AvSettings {
     // called on the thread where Initialize() was called.
     OUTPUT_RESTRICTIONS_CHANGED = 4,
 
+    // This event shall be fired whenever the type of volume control provided
+    // by the device is changed, for e.g., when the device is connected or
+    // disconnected to HDMI sinks
+    AUDIO_VOLUME_CONTROL_TYPE_CHANGED = 5,
+
     // This event should be fired when the device is connected to HDMI sinks.
     HDMI_CONNECTED = 100,
 
@@ -133,12 +155,12 @@ class AvSettings {
   // Returns true if successful.
   virtual bool KeepSystemAwake(int time_ms) = 0;
 
-  // Whether or not the device is a master volume system, i.e the system volume
-  // is changed, but not attenuated. For example, normal TVs, devices of CEC
-  // audio controls, and audio devices are master volume systems.
-  // The counter examples are Chromecast (which doesn't do CEC audio controls)
-  // and Nexus Player (which has volume fixed).
-  virtual bool IsMasterVolumeDevice() = 0;
+  // Returns the type of volume control, i.e. MASTER_VOLUME, FIXED_VOLUME or
+  // ATTENUATION_VOLUME. For example, normal TVs, devices of CEC audio
+  // controls, and audio devices are master volume systems. The counter
+  // examples are Chromecast (which doesn't do CEC audio controls) and
+  // Nexus Player which is fixed volume.
+  virtual AudioVolumeControlType GetAudioVolumeControlType() = 0;
 
   // Returns the current volume level, which must be from 0.0 (inclusive) to
   // 1.0 (inclusive).