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/CSSEngineImpl.java
String tmp = ce.getName();
				if (tmp.equals("provider")) {
					try {
						Object tmp2 = ce.createExecutableExtension("class");
						for (IConfigurationElement ce2 : ce.getChildren()) {
							String widget = ce2.getAttribute("class");
							widgetsMap.put(widget, tmp2);
						}
					} catch (CoreException e1) {
						
						e1.printStackTrace();
					}
				}
			}
		}
		
		super.registerCSSValueConverter(CSSValueBooleanConverterImpl.INSTANCE);
	}
	public CSSEngineImpl(ExtendedDocumentCSS documentCSS) {
		super(documentCSS);
		
		super.registerCSSValueConverter(CSSValueBooleanConverterImpl.INSTANCE);
	}
	public CSSParser makeCSSParser() {
		
		ICSSParserFactory factory = CSSParserFactory.newInstance();
		CSSParser parser = factory.makeCSSParser();
		
		parser.setSelectorFactory(CSSSelectorFactoryImpl.INSTANCE);