Bug 318944 CSSSWTEngineImpl leaks memory
CSSSWTEngineImpl stores too many element contexts. In a memory snapshot, the HashMap size was 15559. This is most probably a leak.
bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/AbstractCSSEngine.java
Object tmp = widgetsMap.get(element.getClass().getName());
			if (tmp == null) {
				Class parent = element.getClass();
				do {
					parent = parent.getSuperclass();
					tmp = widgetsMap.get(parent.getName());
				} while (tmp == null && parent != Object.class);
			}
			
			elementProvider = (IElementProvider) tmp;
			elt = elementProvider.getElement(element, this);
		}
		if (elt != null) {
			if (elementContext == null) {
				elementContext = new CSSElementContextImpl();
				getElementsContext().put(getNativeWidget(element),
						elementContext);
			}
			elementContext.setElementProvider(elementProvider);
			elementContext.setElement(elt);
			if (elt instanceof CSSStylableElement) {
					
					((CSSStylableElement)elt).initialize();
			}
		}
		return elt;
	}
	public Object getDocument() {
		return null;
	}