elm_code: Always render N new lines (buffer).

If we don't have a buffer here you CAN lose the race when scrolling.
As there is a check later in the flow, we can just use a padding
of 64 instead of checking the range. This ensures that scrolling is
smooth and content is always rendered throughout an aggressive
scroll.

src/lib/elementary/elm_code_widget.c

@@ -2121,7 +2121,7 @@ _elm_code_widget_resize(Elm_Code_Widget *widget, Elm_Code_Line *newline)
    if (!newline && viewport)
      {
         /* Where possible render additional lines to the viewport. */
-        _elm_code_widget_fill_range(widget, pd, first_row, last_row + 64 < (unsigned int) h ? last_row + 64 : last_row, NULL);
+        _elm_code_widget_fill_range(widget, pd, first_row, last_row + 64, NULL);
         return;
      }