Add arbitrary keys to VC

Change-Id: I3a26665a861c428ffb40b2387437dcc4296b461c
diff --git a/dev/js/src/vc/prefix.js b/dev/js/src/vc/prefix.js
new file mode 100644
index 0000000..5deefe4
--- /dev/null
+++ b/dev/js/src/vc/prefix.js
@@ -0,0 +1,21 @@
+define(['menu/prefix'], function (prefixClass) {
+  return {
+
+    /**
+     * Create prefix object for the hint helper menu.
+     */
+    create : function (params) {
+      return Object.create(prefixClass).
+	      upgradeTo(this)._init(params);
+    },
+
+    /**
+     * Override the prefix action.
+     */
+    onclick : function (e) {
+      var m = this.menu();
+      var value = this.value();
+      m.release(value, "string");
+    }
+  };
+});