Set up hdmi output device default volume to 100.

chromeos/audio/cras_audio_handler.h

Index: chromeos/audio/cras_audio_handler.h
diff --git a/chromeos/audio/cras_audio_handler.h b/chromeos/audio/cras_audio_handler.h
index b95f123bb3da5f7c6e6d1c8dadf89c7f2cf418e7..48e0376591f89a1f9aee61ce179b287841c565bf 100644
--- a/chromeos/audio/cras_audio_handler.h
+++ b/chromeos/audio/cras_audio_handler.h
@@ -20,17 +20,6 @@
 class PrefRegistrySimple;
 class PrefService;
 
-namespace {
-
-// Default value for the volume pref, as a percent in the range [0.0, 100.0].
-const double kDefaultVolumeGainPercent = 75.0;
-
-// Values used for muted preference.
-const int kPrefMuteOff = 0;
-const int kPrefMuteOn = 1;
-
-}  // namespace
-
 namespace chromeos {
 
 class AudioDevicesPrefHandler;