Bug 65444 [R21PRES] Close button shown when views not closeable
RC1 build - run the browser example using the R2.1 presentation - the views have close buttons in the titlebar, but should not because the perspective has fixed="true" (meaning that all initial views are non-moveable and non-closeable)
bundles/org.eclipse.ui.presentations.r21/src/org/eclipse/ui/internal/presentations/R21BasicStackPresentation.java
/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.skins.Presentation#setVisible(boolean)
	 */
	public void setVisible(boolean isVisible) {
		if (current != null) {
			current.setVisible(isVisible);
		}
		paneFolder.getControl().setVisible(isVisible);
	}
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.skins.Presentation#setState(int)
	 */
	public void setState(int state) {
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.skins.Presentation#getSystemMenuManager()
	 */
	public IMenuManager getSystemMenuManager() {
		return systemMenuManager;
	}
	
	/**
	 * @param point
	 */
	protected void showSystemMenu(Point point) {
		Menu aMenu = systemMenuManager.createContextMenu(paneFolder.getControl().getParent());
		systemMenuManager.update(true);
		aMenu.setLocation(point.x, point.y);