Fix - detect element width/height from style

If HTML layout does not display main element and therefore detected dimensions are 0, try to extract width and height from style. In many practical situation it will be perfect match

Author: linev

modules/base/BasePainter.mjs

@@ -646,6 +646,14 @@ class BasePainter {
 
       rect.changed = false;
 
+      if (!rect.width && !rect.height && !main.empty() && main.attr('style')) {
+         const ws = main.style('width'), hs = main.style('height');
+         if (isStr(ws) && isStr(hs) && ws.match(/^\d+px$/) && hs.match(/^\d+px$/)) {
+            rect.width = parseInt(ws.slice(0, ws.length-2));
+            rect.height = parseInt(hs.slice(0, hs.length-2));
+         }
+      }
+
       if (old_h && old_w && (old_h > 0) && (old_w > 0)) {
          if ((old_h !== rect.height) || (old_w !== rect.width))
             rect.changed = (check_level > 1) || (rect.width / old_w < 0.99) || (rect.width / old_w > 1.01) || (rect.height / old_h < 0.99) || (rect.height / old_h > 1.01);