Add Voice Assist key.

Bug: 16292420
Change-Id: I607fadc2edf673079bfd9f7406e6e45603474957
diff --git a/include/android/keycodes.h b/include/android/keycodes.h
index da7302d..813d411 100644
--- a/include/android/keycodes.h
+++ b/include/android/keycodes.h
@@ -273,7 +273,8 @@
     AKEYCODE_11              = 227,
     AKEYCODE_12              = 228,
     AKEYCODE_LAST_CHANNEL    = 229,
-    AKEYCODE_TV_DATA_SERVICE = 230
+    AKEYCODE_TV_DATA_SERVICE = 230,
+    AKEYCODE_VOICE_ASSIST    = 231
 
     // NOTE: If you add a new keycode here you must also add it to several other files.
     //       Refer to frameworks/base/core/java/android/view/KeyEvent.java for the full list.