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
}
			
			if (PreferenceConstants.EDITOR_FOLDING_PROVIDER.equals(property)) {
				if (sourceViewer instanceof ProjectionViewer) {
					ProjectionViewer projectionViewer= (ProjectionViewer) sourceViewer;
					if (fProjectionModelUpdater != null)
						fProjectionModelUpdater.uninstall();
					
					fProjectionModelUpdater= JavaPlugin.getDefault().getFoldingStructureProviderRegistry().getCurrentFoldingProvider();
					if (fProjectionModelUpdater != null) {
						fProjectionModelUpdater.install(this, projectionViewer);
					}
				}
				return;
			}
			
		} finally {
			super.handlePreferenceStoreChanged(event);
		}
	}
	
	/**
	 * Initializes the given viewer's colors.
	 * 
	 * @param viewer the viewer to be initialized
	 * @since 3.0
	 */
	protected void initializeViewerColors(ISourceViewer viewer) {
		
	}