Bug 36519 [call hierarchy] ability to copy the view's content to the clipboard
we should add the ability to copy the view's content to the clipboard (it may be useful for people to take a pic of the callgraph and show to other people, for example)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/callhierarchy/CallHierarchyViewPart.java
Object structuredSelection = ((IStructuredSelection) selection).getFirstElement();
            if (structuredSelection instanceof MethodWrapper) {
                MethodWrapper methodWrapper = (MethodWrapper) structuredSelection;
                CallLocation firstCall = methodWrapper.getMethodCall()
                                                      .getFirstCallLocation();
                if (firstCall != null) {
                    CallHierarchyUI.jumpToLocation(firstCall);
                } else {
                    CallHierarchyUI.jumpToMember(methodWrapper.getMember());
                }
            } else if (structuredSelection instanceof CallLocation) {
                CallHierarchyUI.jumpToLocation((CallLocation) structuredSelection);
            }
        }
    }
    /**
     *
     */
    public void refresh() {
        setCalleeRoot(null);
        setCallerRoot(null);
        updateView();
    }
    public void saveState(IMemento memento) {
        if (fPagebook == null) {
            
            if (fMemento != null) { 
                memento.putMemento(fMemento);
            }
            return;