Remove unused shadow

package com.android.settings.testutils.shadow;

import android.content.Context;

import com.android.settings.network.MobileNetworkPreferenceController;

import org.robolectric.annotation.Implementation;

import org.robolectric.annotation.Implements;

@Implements(MobileNetworkPreferenceController.class)

public class ShadowMobileNetworkPreferenceController {

    private static boolean mIsRestricted = false;

    public void __constructor__(Context context) {

    }

    @Implementation

    public boolean isAvailable() {

        return mIsRestricted ? false : true;

    }

    @Implementation

    public boolean isUserRestricted() {

        return mIsRestricted;

    }

    public static void setRestricted(boolean restricted) {

        mIsRestricted = restricted;

    }

}