Make sure the ProxyProperties is always present.

Lets people know that it's non-null, though the InetAddr inside may be.

bug:3305689
Change-Id: I0fe16a9ef1feba987680c419fa2dc0e00e400d91
diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index feb7b63..a84ba78 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -2154,6 +2154,7 @@
     }
 
     private void sendProxyBroadcast(ProxyProperties proxy) {
+        if (proxy == null) proxy = new ProxyProperties("", 0, "");
         log("sending Proxy Broadcast for " + proxy);
         Intent intent = new Intent(Proxy.PROXY_CHANGE_ACTION);
         intent.addFlags(Intent.FLAG_RECEIVER_REPLACE_PENDING);