Adding onDisconnect.

Change-Id: If1499f1c80a98abe5b1874f4e92d7959281d1b07
diff --git a/src/com/android/incallui/CallHandlerService.java b/src/com/android/incallui/CallHandlerService.java
index 490adc0..4681f6a 100644
--- a/src/com/android/incallui/CallHandlerService.java
+++ b/src/com/android/incallui/CallHandlerService.java
@@ -62,6 +62,9 @@
             intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
             startActivity(intent);
         }
+
+        public void onDisconnect(int callId) {
+        }
     };
 
     private void logD(String message) {