Bug 37464 call hierarchy: Should not use working copies
The call hierarchy should not use working copies of compilation units since these may go away (e.g. when an editor is closed).
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/callhierarchy/CallHierarchyViewPart.java
getSite().getPage().bringToTop(editorPart);
                    if (editorPart instanceof ITextEditor) {
                        ITextEditor editor = (ITextEditor) editorPart;
                        editor.selectAndReveal(callLocation.getStart(),
                            (callLocation.getEnd() - callLocation.getStart()));
                    }
                }
            } else {
                IEditorPart editorPart = CallHierarchyUI.isOpenInEditor(elem);
                getSite().getPage().bringToTop(editorPart);
                EditorUtility.revealInEditor(editorPart,
                    ((MethodWrapper) elem).getMember());
            }
        } else if (elem instanceof IJavaElement) {
            IEditorPart editorPart = EditorUtility.isOpenInEditor(elem);
            if (editorPart != null) {
                
                getSite().getPage().bringToTop(editorPart);
                EditorUtility.revealInEditor(editorPart, (IJavaElement) elem);
                
            }
        }
    }
    /**
     * Returns the current selection.
     */
    protected ISelection getSelection() {
        return getSite().getSelectionProvider().getSelection();
    }
    protected void fillLocationViewerContextMenu(IMenuManager menu) {