Cleanup of process-specific DNS.

Removes entries sooner.  A bug.
Doesn't add one for phone process at all.  This was intended to be removed long ago.

bug: 2329900

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

@@ -660,8 +660,8 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             tracker =  mNetTrackers[usedNetworkType];
             if(usedNetworkType != networkType) {
                 Integer currentPid = new Integer(pid);
-                reassessPidDns(pid, true);
                 mNetRequestersPids[usedNetworkType].remove(currentPid);
+                reassessPidDns(pid, true);
                 if (mNetRequestersPids[usedNetworkType].size() != 0) {
                     if (DBG) Log.d(TAG, "not tearing down special network - " +
                            "others still using it");