use sp for scaled footer

mastodon/src/main/java/org/joinmastodon/android/ui/displayitems/FooterStatusDisplayItem.java

@@ -182,7 +182,7 @@ public class FooterStatusDisplayItem extends StatusDisplayItem{
 				touchingView = v;
 				// 28dp to center in middle of icon, because:
 				// (icon width = 24dp) / 2 + (paddingStart = 8dp) + (paddingHorizontal = 8dp)
-				v.setPivotX(V.dp(28));
+				v.setPivotX(UiUtils.sp(v.getContext(), 28));
 				v.animate().scaleX(0.85f).scaleY(0.85f).setInterpolator(CubicBezierInterpolator.DEFAULT).setDuration(75).start();
 				if (disabled) return true;
 				v.postDelayed(longClickRunnable, ViewConfiguration.getLongPressTimeout());

mastodon/src/main/java/org/joinmastodon/android/ui/utils/UiUtils.java

@@ -1407,6 +1407,16 @@ public class UiUtils {
 		}
 	}
 
+	/**
+	 * Scale the input value according to the device's scaled display density
+	 * @param sp Input value in scale-independent pixels (sp)
+	 * @return Scaled value in physical pixels (px)
+	 */
+	public static int sp(Context context, float sp){
+		// TODO: replace with V.sp in next AppKit version
+		return Math.round(sp*context.getApplicationContext().getResources().getDisplayMetrics().scaledDensity);
+	}
+
 	/**
 	 * Wraps a View.OnClickListener to filter multiple clicks in succession.
 	 * Useful for buttons that perform some action that changes their state asynchronously.

mastodon/src/main/res/layout/display_item_footer.xml

@@ -2,8 +2,8 @@
 <org.joinmastodon.android.ui.views.MaxWidthFrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
 	xmlns:tools="http://schemas.android.com/tools"
 	xmlns:app="http://schemas.android.com/apk/res-auto"
-	android:maxWidth="600dp"
-	app:defaultWidth="450dp"
+	android:maxWidth="600sp"
+	app:defaultWidth="450sp"
 	android:layout_width="match_parent"
 	android:layout_height="wrap_content">