Revert "Fix test case fail"

This reverts commit 6d387e4a5f.

Reason for revert: collateral damage for b/121116425

Change-Id: I3ba716e283bf466ad8603c1d8c64861febec9a8c

src/com/android/settings/core/InstrumentedPreferenceFragment.java

@@ -22,7 +22,6 @@ import android.text.TextUtils;
 import android.util.Log;
 
 import androidx.annotation.XmlRes;
-import androidx.preference.Preference;
 import androidx.preference.PreferenceScreen;
 
 import com.android.settings.overlay.FeatureFactory;
@@ -79,14 +78,6 @@ public abstract class InstrumentedPreferenceFragment extends ObservablePreferenc
         updateActivityTitleWithScreenTitle(getPreferenceScreen());
     }
 
-    @Override
-    public <T extends Preference> T findPreference(CharSequence key) {
-        if (key == null) {
-            return null;
-        }
-        return super.findPreference(key);
-    }
-
     protected final Context getPrefContext() {
         return getPreferenceManager().getContext();
     }