Bug 52474 UI Blocked when opening Java Perspective during CVS check out
build I20040218 - start eclipse with a new workspace - switch to CVS Repository Exploring perspective - check out a number of projects ( i checkout Platform UI module) - now attempt to switch to the Java Perspective NOTE that at this point the "UI is blocked" dialog is opened. Probably due to the fact that starting the Java Perspective requires the workbench lock? The point here is that this will be a common pattern and it would be nice if we could investigate makeing this scenario work more smoothly.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
* Create the KeyListener for doing the refresh on the viewer.
	 */
	private void initKeyListener() {
		fViewer.getControl().addKeyListener(new KeyAdapter() {
			public void keyReleased(KeyEvent event) {
				fActionSet.handleKeyEvent(event);
			}
		});
	}
	/**
	 * An editor has been activated.  Set the selection in this Packages Viewer
	 * to be the editor's input, if linking is enabled.
	 */
	void editorActivated(IEditorPart editor) {
		if (!isLinkingEnabled())  
			return;
		Object input= getElementOfInput(editor.getEditorInput());
		if (input == null) 
			return;
		if (!inputIsSelected(editor.getEditorInput()))
			showInput(input);
	}
	private boolean inputIsSelected(IEditorInput input) {
		IStructuredSelection selection= (IStructuredSelection)fViewer.getSelection();
		if (selection.size() != 1) 
			return false;
		IEditorInput selectionAsInput= null;
		try {
			selectionAsInput= EditorUtility.getEditorInput(selection.getFirstElement());
		} catch (JavaModelException e1) {