Introduce KeyboardCodesSet.java and remove keycodes.xml

Change-Id: Icfd6d06f47425aa037682d22c895548ba6f047d8
diff --git a/java/res/xml/keys_parentheses.xml b/java/res/xml/keys_parentheses.xml
index 6853bf1..502a84e 100644
--- a/java/res/xml/keys_parentheses.xml
+++ b/java/res/xml/keys_parentheses.xml
@@ -23,10 +23,10 @@
 >
     <Key
         latin:keyLabel="("
-        latin:code="@integer/keycode_for_left_parenthesis"
+        latin:code="!code/key_left_parenthesis"
         latin:moreKeys="@string/more_keys_for_left_parenthesis" />
     <Key
         latin:keyLabel=")"
-        latin:code="@integer/keycode_for_right_parenthesis"
+        latin:code="!code/key_right_parenthesis"
         latin:moreKeys="@string/more_keys_for_right_parenthesis" />
 </merge>