Update ui-grid-column-resizer.js

Fix for undefined coldef being thrown on resize of pinned column

packages/resize-columns/src/js/ui-grid-column-resizer.js

@@ -119,6 +119,9 @@
  if (position === 'left') {
  // Get the column to the left of this one
  var colIndex = renderContainer.visibleColumnCache.indexOf(col);
+ if (colIndex === 0) {
+ return renderContainer.visibleColumnCache[0];
+ }
  return renderContainer.visibleColumnCache[colIndex - 1 * rtlMultiplier];
  } else {
  return col;