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/typehierarchy/TypeHierarchyViewPart.java
/**
	 * Sets the input to a new type
	 * @deprecated 
	 */
	public void setInput(IType type) {
		setInputElement(type);
	}	
	
	/**
	 * Returns the input element of the type hierarchy.
	 * Can be of type <code>IType</code> or <code>IPackageFragment</code>
	 */	
	public IJavaElement getInputElement() {
		return fInputElement;
	}			
		
	/**
	 * Sets the input to a new element.
	 */	
	public void setInputElement(IJavaElement element) {
		if (element != null) {
			if (element instanceof IMember) {
				if (element.getElementType() != IJavaElement.TYPE) {
					element= ((IMember) element).getDeclaringType();
				}				
				ICompilationUnit cu= ((IMember) element).getCompilationUnit();
				if (cu != null && cu.isWorkingCopy()) {
					element= cu.getOriginal(element);
					if (!element.exists()) {