Fix a11y service icons are tiny after changing display size to "Largest"

Root cause: Scaled down non vector drawable to to avoid crashing Settings
Solution: Enlarge the maxWidth & maxHeight from 500 to 600

Bug: 195975294
Test: manual test
Change-Id: I9d771cfaa7cf3eed37265219c082b6337fa5c063

src/com/android/settings/Utils.java

@@ -1013,7 +1013,8 @@ public final class Utils extends com.android.settingslib.Utils {
         Drawable safeIcon = icon;
 
         if ((icon != null) && !(icon instanceof VectorDrawable)) {
-            safeIcon = getSafeDrawable(icon, 500, 500);
+            safeIcon = getSafeDrawable(icon,
+                    /* MAX_DRAWABLE_SIZE */ 600, /* MAX_DRAWABLE_SIZE */ 600);
         }
 
         return safeIcon;