Add calls for NFC WSC token creation

Expose interface for generating Wifi Simple
Configuration tokens from supplicant.

Change-Id: Ie310a32f529c0330340e045aee561dc434aeee3e

wifi/java/android/net/wifi/IWifiManager.aidl

@@ -124,5 +124,7 @@ interface IWifiManager
     boolean isBatchedScanSupported();
 
     void pollBatchedScan();
+
+    String getWpsNfcConfigurationToken(int netId);
 }
 

wifi/java/android/net/wifi/WifiManager.java

@@ -877,6 +877,21 @@ public class WifiManager {
         } catch (RemoteException e) { }
     }
 
+    /**
+     * Creates a configuration token describing the network referenced by {@code netId}
+     * of MIME type application/vnd.wfa.wsc. Can be used to configure WiFi networks via NFC.
+     *
+     * @return hex-string encoded configuration token
+     * @hide
+     */
+    public String getWpsNfcConfigurationToken(int netId) {
+        try {
+            return mService.getWpsNfcConfigurationToken(netId);
+        } catch (RemoteException e) {
+            return null;
+        }
+    }
+
     /**
      * Return dynamic information about the current Wi-Fi connection, if any is active.
      * @return the Wi-Fi information, contained in {@link WifiInfo}.