Bug 63769 Endless loop after Show in Package Explorer
there are situations when you run in an endless loop in show in package explorer when the action is attempting to reveal an element.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
boolean isExpandable(Object element) {
		if (fViewer == null)
			return false;
		return fViewer.isExpandable(element);
	}
	void setWorkingSetName(String workingSetName) {
		fWorkingSetName= workingSetName;
	}
	
	/**
	 * Updates the title text and title tool tip.
	 * Called whenever the input of the viewer changes.
	 */ 
	void updateTitle() {		
		Object input= fViewer.getInput();
		String viewName= getConfigurationElement().getAttribute("name"); 
		if (input == null
			|| (input instanceof IJavaModel)) {
			setTitle(viewName);
			setTitleToolTip(""); 
		} else {
			String inputText= JavaElementLabels.getTextLabel(input, AppearanceAwareLabelProvider.DEFAULT_TEXTFLAGS);
			String title= PackagesMessages.getFormattedString("PackageExplorer.argTitle", new String[] { viewName, inputText }); 
			setTitle(title);
			setTitleToolTip(getToolTipText(input));
		} 
	}
	
	/**
	 * Sets the decorator for the package explorer.