Introduce a WifiTrackerLibProvider.

This make the WifiTrackerLib can be customized.

Bug: 149540986
Test: manual test wifi picker, and atest com.android.settings
Change-Id: I1418ae39c895ce2ff87f18005a226a4835f9e083

tests/unit/src/com/android/settings/testutils/FakeFeatureFactory.java

@@ -41,6 +41,7 @@ import com.android.settings.search.SearchFeatureProvider;
 import com.android.settings.security.SecurityFeatureProvider;
 import com.android.settings.slices.SlicesFeatureProvider;
 import com.android.settings.users.UserFeatureProvider;
+import com.android.settings.wifi.WifiTrackerLibProvider;
 import com.android.settingslib.core.instrumentation.MetricsFeatureProvider;
 
 /**
@@ -72,6 +73,8 @@ public class FakeFeatureFactory extends FeatureFactory {
     public SearchFeatureProvider searchFeatureProvider;
     public ContextualCardFeatureProvider mContextualCardFeatureProvider;
 
+    public WifiTrackerLibProvider wifiTrackerLibProvider;
+
     /**
      * Call this in {@code @Before} method of the test class to use fake factory.
      */
@@ -106,6 +109,7 @@ public class FakeFeatureFactory extends FeatureFactory {
         mBluetoothFeatureProvider = mock(BluetoothFeatureProvider.class);
         mAwareFeatureProvider = mock(AwareFeatureProvider.class);
         mFaceFeatureProvider = mock(FaceFeatureProvider.class);
+        wifiTrackerLibProvider = mock(WifiTrackerLibProvider.class);
     }
 
     @Override
@@ -217,4 +221,9 @@ public class FakeFeatureFactory extends FeatureFactory {
     public FaceFeatureProvider getFaceFeatureProvider() {
         return mFaceFeatureProvider;
     }
+
+    @Override
+    public WifiTrackerLibProvider getWifiTrackerLibProvider() {
+        return wifiTrackerLibProvider;
+    }
 }