Get rid of headingStoreTextColorValue

app/src/main/java/protect/card_locker/LoyaltyCardViewActivity.java

@@ -8,7 +8,6 @@ import android.os.Build;
 import android.os.Bundle;
 
 import androidx.constraintlayout.widget.ConstraintLayout;
-import androidx.core.graphics.ColorUtils;
 import androidx.core.graphics.drawable.DrawableCompat;
 import androidx.core.widget.TextViewCompat;
 import androidx.appcompat.app.ActionBar;
@@ -36,7 +35,6 @@ import protect.card_locker.preferences.Settings;
 public class LoyaltyCardViewActivity extends AppCompatActivity
 {
     private static final String TAG = "Catima";
-    private static final double LUMINANCE_MIDPOINT = 0.5;
 
     TextView cardIdFieldView;
     TextView noteView;
@@ -223,7 +221,7 @@ public class LoyaltyCardViewActivity extends AppCompatActivity
         collapsingToolbarLayout.setBackgroundColor(backgroundHeaderColor);
 
         // If the background is very bright, we should use dark icons
-        backgroundNeedsDarkIcons = (ColorUtils.calculateLuminance(backgroundHeaderColor) > LUMINANCE_MIDPOINT);
+        backgroundNeedsDarkIcons = Utils.needsDarkForeground(backgroundHeaderColor);
         ActionBar actionBar = getSupportActionBar();
         if(actionBar != null)
         {