Change superclass to InstrumentedFragment.

- for fragments that do not implement the preference screen, change them
to inherit from InstrumentedFragment instead.

Change-Id: I791c2634024bd2c248efea955be5c680180d735c
Fixes: 68277111
Test: make RunSettingsRoboTests

src/com/android/settings/network/NetworkScorerPicker.java

@@ -50,7 +50,6 @@ public class NetworkScorerPicker extends InstrumentedPreferenceFragment implemen
     @Override
     public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
         super.onCreatePreferences(savedInstanceState, rootKey);
-        addPreferencesFromResource(R.xml.network_scorer_picker_prefs);
         updateCandidates();
     }
 
@@ -69,6 +68,11 @@ public class NetworkScorerPicker extends InstrumentedPreferenceFragment implemen
         return view;
     }
 
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.network_scorer_picker_prefs;
+    }
+
     @VisibleForTesting
     public void updateCandidates() {
         final PreferenceScreen screen = getPreferenceScreen();