Use keyboardSet extra value of subtype to specify layout type

Change-Id: Ice1f345a08a8d760e3b847c885c4072e3e142c97
diff --git a/java/proguard.flags b/java/proguard.flags
index 2ee1a26..44f8581 100644
--- a/java/proguard.flags
+++ b/java/proguard.flags
@@ -40,7 +40,7 @@
   void setLogFileManager(...);
 }
 
--keep class com.android.inputmethod.keyboard.KeyboardSet$Builder {
+-keep class com.android.inputmethod.keyboard.KeyboardLayoutSet$Builder {
   void setTouchPositionCorrectionEnabled(...);
 }