Bug 327585 Commands, Handlers, and keybindings should use leaf lookup
bundles/org.eclipse.e4.core.commands/src/org/eclipse/e4/core/commands/internal/HandlerServiceImpl.java
public final static String H_ID = "handler::"; 
	public final static String PARM_MAP = "parmMap::"; 
	final static String LOOKUP_HANDLER = "handler"; 
	public static Object lookUpHandler(IEclipseContext context, String commandId) {
		return context.getActiveLeaf().get(H_ID + commandId);
	}
	private IEclipseContext context;
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.core.commands.EHandlerService#activateHandler(java.lang.String,
	 * java.lang.Object)
	 */