drools-eclipse/org.guvnor.tools/src/org/guvnor/tools/utils/PlatformUtils.java
public static void updateDecoration() {
        final IWorkbench workbench = Activator.getDefault().getWorkbench();
        workbench.getDisplay().syncExec(new Runnable() {
            public void run() {
                IDecoratorManager manager = workbench.getDecoratorManager();
                manager.update(GuvnorDecorator.DECORATOR_ID);
            }
        });
    }
public static void updateDecoration() {
        final IWorkbench workbench = Activator.getDefault().getWorkbench();
        workbench.getDisplay().syncExec(new Runnable() {
            public void run() {
                IDecoratorManager manager = workbench.getDecoratorManager();
                manager.update(GuvnorDecorator.DECORATOR_ID);
            }
        });
    }
Causes the platform to update Guvnor decoration notions.