Update state to failed if the VPN fails to connect.

Without this, the VPN settings dialog stays in "Connecting..."
forever.

Bug: 17140195
Change-Id: I4771be464384b62114839523fb2a6b36aa6520ee

services/core/java/com/android/server/connectivity/Vpn.java

@@ -1263,6 +1263,7 @@ public class Vpn {
                 }
             } catch (Exception e) {
                 Log.i(TAG, "Aborting", e);
+                updateState(DetailedState.FAILED, e.getMessage());
                 exit();
             } finally {
                 // Kill the daemons if they fail to stop.