Control UI behavior according to different Wi-Fi DPP intents.

When it's a configurator from Settings, the cancel button of WifiDppChooseSavedWifiNetworkFragment
should pop back stack. When it's a configurator from a camera app, the cancel button of
WifiDppChooseSavedWifiNetworkFragment should finish host activity.

Bug: 120517242
Test: manual test
Change-Id: Ia0fb0daf16c94ecd62aa6d357405fcd529935d2f

src/com/android/settings/wifi/dpp/WifiDppConfiguratorActivity.java

@@ -314,8 +314,6 @@ public class WifiDppConfiguratorActivity extends InstrumentedActivity implements
 
     @Override
     public void onClickChooseDifferentNetwork() {
-        mWifiNetworkConfig = null;
-
         showChooseSavedWifiNetworkFragment(/* addToBackStack */ true);
     }