Sets the background drawing mode to the argument which should
be one of the following constants defined in class <code>SWT</code>:
<code>INHERIT_NONE</code>, <code>INHERIT_DEFAULT</code>,
<code>INHERIT_FORCE</code>.
@param mode the new background mode
@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 background drawing mode to the argument which should be one of the following constants defined in class <code>SWT</code>: <code>INHERIT_NONE</code>, <code>INHERIT_DEFAULT</code>, <code>INHERIT_FORCE</code>.
@param mode the new background mode
@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>
@see SWT
@since 3.2