Bug 71546 CVS decoration not updated for jars after a commit
When committing a jar that is in the classpath, the CVS decoration is not updated in the package view. The decoration is first updated when closing the package view an opening it again.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/ResourceToItemsMapper.java
*/	
	public void removeFromMap(Object element, Item item) {
		IResource resource= getCorrespondingResource(element);
		if (resource != null) {
			Object existingMapping= fResourceToItem.get(resource);
			if (existingMapping == null) {
				return;
			} else if (existingMapping instanceof Item) {
				fResourceToItem.remove(resource);
			} else { 
				List list= (List) existingMapping;
				list.remove(item);
				if (list.isEmpty()) {
					fResourceToItem.remove(list);
					releaseList(list);
				}
			}
		}
	}
	
	private List getNewList() {
		if (!fReuseLists.isEmpty()) {
			return (List) fReuseLists.pop();
		}
		return new ArrayList(2);
	}
	
	private void releaseList(List list) {
		if (fReuseLists.size() < NUMBER_LIST_REUSE) {
			fReuseLists.push(list);