Bug 176043 [Commands] Need to be able to restore the toolbar without breking plug-in boundaries
bundles/org.eclipse.ui.carbon/src/org/eclipse/ui/carbon/CarbonUIEnhancer.java
boolean coolBarInitiallyVsible = ((WorkbenchWindow) window)
				.getCoolBarVisible();
		boolean perspectiveBarInitiallyVsible = ((WorkbenchWindow) window)
				.getPerspectiveBarVisible();
		if (coolBarInitiallyVsible || perspectiveBarInitiallyVsible) {
			
			
			Shell shell = window.getShell();
			int windowHandle = OS.GetControlOwner(shell.handle);
			OS.ChangeWindowAttributes(windowHandle,
					OS.kWindowToolbarButtonAttribute, 0);
		}
	}
	
	/**
	 * Hook the window toolbar button to toggle the visibility of the coolbar
	 * and perspective bar.
	 * 
	 * @since 3.2
	 */
    protected void hookToolbarButtonCallback() {
		Object target = new Target();
		
	    final Callback commandCallback = new Callback(target, "toolbarProc", 3); 
        int commandProc = commandCallback.getAddress();
        if (commandProc == 0) {
            commandCallback.dispose();
            return;