Enhance WPS

- Add a cancel API
- Add more error reporting on WPS
- Fix network status reporting that showed up with new implementation

Change-Id: I499796c80d16d18df95fb702d029aa7e7283b603

services/java/com/android/server/WifiService.java

@@ -297,6 +297,10 @@ public class WifiService extends IWifiManager.Stub {
                     mWifiStateMachine.sendMessage(Message.obtain(msg));
                     break;
                 }
+                case WifiManager.CANCEL_WPS: {
+                    mWifiStateMachine.sendMessage(Message.obtain(msg));
+                    break;
+                }
                 case WifiManager.DISABLE_NETWORK: {
                     mWifiStateMachine.sendMessage(Message.obtain(msg));
                     break;