Checks that this class can be subclassed. <p> IMPORTANT: See the comment in <code>Widget.checkSubclass()</code>. </p>
@exception SWTException <ul> <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> </ul>
@see Widget#checkSubclass
See Implementation
Checks that this class can be subclassed. <p> IMPORTANT: See the comment in <code>Widget.checkSubclass()</code>. </p>
@exception SWTException <ul> <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> </ul>
@see Widget#checkSubclass