Restart Wi-Fi tethering automatically if configuration change

- When the Wi-Fi Hotspot is already started, if the user changes the configuration, the Wi-Fi Hotspot will be restarted automatically.

- When the Wi-Fi hotspot restarts, display a circle on the screen to indicate that it is processing.

Bug: 245258763
Test: manual test
atest -c WifiTetherSettingsTest \
         WifiHotspotSpeedSettingsTest
atest -c WifiHotspotRepositoryTest \
         WifiHotspotSecuritySettingsTest \
         WifiHotspotSecurityViewModelTest \
         WifiHotspotSpeedViewModelTest \
         WifiTetherViewModelTest

Change-Id: I6fdd5892916703095f28d0589ebc3b7dd59fcd61

src/com/android/settings/wifi/tether/WifiHotspotSpeedSettings.java

@@ -24,6 +24,8 @@ import static com.android.settings.wifi.repository.WifiHotspotRepository.SPEED_6
 import android.app.settings.SettingsEnums;
 import android.os.Bundle;
 
+import androidx.annotation.VisibleForTesting;
+
 import com.android.settings.R;
 import com.android.settings.dashboard.DashboardFragment;
 import com.android.settings.overlay.FeatureFactory;
@@ -80,6 +82,7 @@ public class WifiHotspotSpeedSettings extends DashboardFragment implements
         onSpeedInfoMapDataChanged(mWifiHotspotSpeedViewModel.getSpeedInfoMapData().getValue());
         mWifiHotspotSpeedViewModel.getSpeedInfoMapData()
                 .observe(this, this::onSpeedInfoMapDataChanged);
+        mWifiHotspotSpeedViewModel.getRestarting().observe(this, this::onRestartingChanged);
     }
 
     protected void loadPreferences() {
@@ -117,6 +120,12 @@ public class WifiHotspotSpeedSettings extends DashboardFragment implements
         }
     }
 
+    @VisibleForTesting
+    void onRestartingChanged(Boolean restarting) {
+        log("onRestartingChanged(), restarting:" + restarting);
+        setLoading(restarting, false);
+    }
+
     @Override
     public void onRadioButtonClicked(SelectorWithWidgetPreference emiter) {
         String key = emiter.getKey();