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
}
		
	/**
	 * Returns a segmentation of the given line appropriate for bidi rendering. The default
	 * implementation returns only the string literals of a java code line as segments.
	 * 
	 * @param widgetLineOffset the offset of the line
	 * @param line the content of the line
	 * @return the line's bidi segmentation
	 */
	protected int[] getBidiLineSegments(int widgetLineOffset, String line) {
		if (line != null && line.length() > 0) {
			ISourceViewer sourceViewer= getSourceViewer();
			if (sourceViewer != null) {
				int lineOffset;
				if (sourceViewer instanceof ITextViewerExtension5) {
					ITextViewerExtension5 extension= (ITextViewerExtension5) sourceViewer;
					lineOffset= extension.widgetOffset2ModelOffset(widgetLineOffset);
				} else {
					IRegion visible= sourceViewer.getVisibleRegion();
					lineOffset= visible.getOffset() + widgetLineOffset;
				}
				try {
					return getBidiLineSegments(sourceViewer, lineOffset);
				} catch (BadLocationException x) {
					
				}
			}
		}
		return null;