Expanded area does not re-adjust when columns are pinned

[DmitryEfimenko]

steps to reproduce:

• go to Expandable Grid tutorial
• scroll down to the first demo
• expand one of the rows
• Pin Left column Id on the parent table
• observe that unpinned columns got a scroll bar and its width didn't readjust
• Pin Left column Name on the parent table
• observe that a loading gif is now visible.