Bug 48452 Widget is disposed while closing cool bar
This is the problem that is occurring in the nightly builds. There is something happening where a cool bar is attempting to layout disposed cool bar items.
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ToolBarContributionItem.java
this.minimumItemsToShow = minimumItemsToShow;
	}
	
	/**
	 * Enables or disables chevron support for the cool item. By default, chevron support is 
	 * enabled.
	 * 
	 * @param value <code>true</code> to enable chevron support, <code>false</code> otherwise.
	 */
	public void setUseChevron(boolean value) {
		useChevron = value;	
	}
	
	/**
	 * Returns whether chevron support is enabled.
	 * 
	 * @return <code>true</code> if chevron support is enabled, <code>false</code> otherwise
	 */
	public boolean getUseChevron() {
		return useChevron;
	}
	/**
	 * Returns the current width of the corresponding cool item.
	 * 
	 * @return the current size
	 */
	public int getCurrentWidth() {
		return currentWidth;
	}