Fix infinite recursion.

Bug: 15695506
Change-Id: Id6b16db87ce9cbf980b601799710977205ac53cd
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index c71ea79..d6f9071 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -471,7 +471,7 @@
      * @see #sendRequestAsync
      */
     private Object sendRequest(int command, Object argument) {
-        return sendRequest(command, argument);
+        return sendRequest(command, argument, null);
     }
 
     /**