Bug 55604 [implementation] JavaOutlinePage should dispose CustomFiltersActionGroup
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaOutlinePage.java
JavaPlugin.createStandardGroups(menu);
				
		IStructuredSelection selection= (IStructuredSelection)getSelection();
		fActionGroups.setContext(new ActionContext(selection));
		fActionGroups.fillContextMenu(menu);
	}
	
	/*
	 * @see Page#setFocus()
	 */
	public void setFocus() {
		if (fOutlineViewer != null)
			fOutlineViewer.getControl().setFocus();
	}
	
	/**
	 * Checks whether a given Java element is an inner type.
	 */
	private boolean isInnerType(IJavaElement element) {
		
		if (element != null && element.getElementType() == IJavaElement.TYPE) {
			IType type= (IType)element;
			try {
				return type.isMember();
			} catch (JavaModelException e) {
				IJavaElement parent= type.getParent();
				if (parent != null) {
					int parentElementType= parent.getElementType();
					return (parentElementType != IJavaElement.COMPILATION_UNIT && parentElementType != IJavaElement.CLASS_FILE);