Bug 28575 Hierarchy view updates items twice [type hierarchy]
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
private void updateHierarchyViewer() {
		if (fInputElement == null) {
			fPagebook.showPage(fNoHierarchyShownLabel);
		} else {
			if (getCurrentViewer().containsElements() != null) {
				Runnable runnable= new Runnable() {
					public void run() {
						getCurrentViewer().updateContent(); 
					}
				};
				BusyIndicator.showWhile(getDisplay(), runnable);
				if (!isChildVisible(fViewerbook, getCurrentViewer().getControl())) {
					setViewerVisibility(true);
				}	
			} else {							
				fEmptyTypesViewer.setText(TypeHierarchyMessages.getFormattedString("TypeHierarchyViewPart.nodecl", fInputElement.getElementName()));				 
				setViewerVisibility(false);
			}
		}
	}
	
	private void updateMethodViewer(final IType input) {
		if (!fIsEnableMemberFilter && fCurrentOrientation != VIEW_ORIENTATION_SINGLE) {
			if (input == fMethodsViewer.getInput()) {
				if (input != null) {
					Runnable runnable= new Runnable() {
						public void run() {
							fMethodsViewer.refresh(); 
						}
					};