Bug 75711 AstProvider should not create AST if requested by SelectionListenerWithASTManager
3.1 M2 If SelectionListenerWithASTManager waits for an AST and the editor closes we should not create an AST for that one but return null instead.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaEditor.java
/*
	 * @see AbstractTextEditor#affectsTextPresentation(PropertyChangeEvent)
	 */
	protected boolean affectsTextPresentation(PropertyChangeEvent event) {
		return ((JavaSourceViewerConfiguration)getSourceViewerConfiguration()).affectsTextPresentation(event) || super.affectsTextPresentation(event);
	}
		
	/**
	 * Creates and returns the preference store for this Java editor with the given input.
	 *
	 * @param input The editor input for which to create the preference store
	 * @return the preference store for this editor
	 *
	 * @since 3.0
	 */
	private IPreferenceStore createCombinedPreferenceStore(IEditorInput input) {
		List stores= new ArrayList(3);
		IJavaProject project= EditorUtility.getJavaProject(input);
		if (project != null)
			stores.add(new OptionsAdapter(project.getOptions(false), JavaPlugin.getDefault().getMockupPreferenceStore(), new OptionsAdapter.IPropertyChangeEventFilter() {
				public boolean isFiltered(PropertyChangeEvent event) {
					IJavaElement inputJavaElement= getInputJavaElement();
					IJavaProject javaProject= inputJavaElement != null ? inputJavaElement.getJavaProject() : null;
					if (javaProject == null)
						return true;
					
					return !javaProject.getProject().equals(event.getSource());
				}
				
			}));