Sets the layout which is associated with the receiver to be
the argument which may be null.
@param layout the receiver's new layout or null
@exception SWTException <ul>
<li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
</ul>
Sets the layout which is associated with the receiver to be the argument which may be null.
@param layout the receiver's new layout or null
@exception SWTException <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> </ul>