Implement 'Available via Passpoint' feature

This also fixes the issues related to explicit connection
to passpoint AP, and fixes occassional mention of
'connected via Wi-Fi Assistent'

Change-Id: Ib4de956f2ea29709d0212fbcb392815644800e78

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

@@ -47,6 +47,8 @@ interface IWifiManager
 
     List<WifiConfiguration> getPrivilegedConfiguredNetworks();
 
+    WifiConfiguration getMatchingWifiConfig(in ScanResult scanResult);
+
     int addOrUpdateNetwork(in WifiConfiguration config);
 
     boolean removeNetwork(int netId);

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

@@ -622,6 +622,20 @@ public class WifiManager {
         }
     }
 
+    /**
+     * Returns a WifiConfiguration matching this ScanResult
+     * @param scanResult scanResult that represents the BSSID
+     * @return {@link WifiConfiguration} that matches this BSSID or null
+     * @hide
+     */
+    public WifiConfiguration getMatchingWifiConfig(ScanResult scanResult) {
+        try {
+            return mService.getMatchingWifiConfig(scanResult);
+        } catch (RemoteException e) {
+            return null;
+        }
+    }
+
     /**
      * Add a new network description to the set of configured networks.
      * The {@code networkId} field of the supplied configuration object