Bug 32384 Cannot open type hierarchy after a cancel
JUnit setup 1) open the type hierarchy on TestCase 2) press F4 on Object 3) cancel in progress bar 4) press F4 on Object again ->nothing happens
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
}
			public void partActivated(IWorkbenchPartReference ref) {
				IWorkbenchPart part= ref.getPart(false);
				if (part instanceof IEditorPart)
					editorActivated((IEditorPart) part);
			}
		 	public void partInputChanged(IWorkbenchPartReference ref) {
				IWorkbenchPart part= ref.getPart(false);
				if (part instanceof IEditorPart)
					editorActivated((IEditorPart) part);
		 	};
			public void partBroughtToTop(IWorkbenchPartReference ref) {}
			public void partClosed(IWorkbenchPartReference ref) {}
			public void partDeactivated(IWorkbenchPartReference ref) {}
			public void partOpened(IWorkbenchPartReference ref) {}
		};
		
		fSelectionChangedListener= new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				doSelectionChanged(event);
			}
		};
		
		fLinkingEnabled= PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.LINK_TYPEHIERARCHY_TO_EDITOR);
	}
	/**
	 * Method doPropertyChange.
	 * @param event
	 */
	protected void doPropertyChange(PropertyChangeEvent event) {