Don't clear Global Proxy on boot.

Doesn't clear the global proxy when a deprecated one is not found because
there still may be a non-deprecated global proxy present.

Bug: 10457179
Change-Id: I68e6d5aee7b4940f9315484060c7d82cb8ccfa70

services/java/com/android/server/ConnectivityService.java

@@ -3355,8 +3355,6 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             }
             ProxyProperties p = new ProxyProperties(data[0], proxyPort, "");
             setGlobalProxy(p);
-        } else {
-            setGlobalProxy(null);
         }
     }