Bug 25827 Disposing of MemberFilterActionGroup
Build 2.0.2 and 2.1 When investigating an editor memory leak PR we found out that this group has a dispose method which is never called. When we then called from the editor it throw an exeption (viewer was disposed). Don't know if the group really needs dispose() if so it should get called.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/browsing/MembersView.java
}
		return false;
	}
	
	/**
	 * Answers if the given <code>element</code> is a valid
	 * element for this part.
	 * 
	 * @param 	element	the object to test
	 * @return	<true> if the given element is a valid element
	 */
	protected boolean isValidElement(Object element) {
		if (element instanceof IMember)
			return super.isValidElement(((IMember)element).getDeclaringType());
		else if (element instanceof IImportDeclaration)
			return isValidElement(((IJavaElement)element).getParent());
		else if (element instanceof IImportContainer) {
			Object input= getViewer().getInput();
			if (input instanceof IJavaElement) {
				ICompilationUnit cu= (ICompilationUnit)((IJavaElement)input).getAncestor(IJavaElement.COMPILATION_UNIT);
				if (cu != null) {
					ICompilationUnit importContainerCu= (ICompilationUnit)((IJavaElement)element).getAncestor(IJavaElement.COMPILATION_UNIT);
					return cu.equals(importContainerCu);
				} else {
					IClassFile cf= (IClassFile)((IJavaElement)input).getAncestor(IJavaElement.CLASS_FILE);
					IClassFile importContainerCf= (IClassFile)((IJavaElement)element).getAncestor(IJavaElement.CLASS_FILE);
					return cf != null && cf.equals(importContainerCf);
				}
			}
		}