String contents = tagNode.getContent();
int contentOffset = attributeEnd.getEnd();
Location location = lineInfo.getLocation(contentOffset);
Scanner scanner = new Scanner(
getSource(),
new SubSequenceReader(contents, contentOffset),
errorListener);
scanner.setSourceStart(location.getLineNumber(), location.getColumnNumber());
com.google.dart.engine.scanner.Token firstToken = scanner.tokenize();
Parser parser = new Parser(getSource(), errorListener);
CompilationUnit unit = parser.parseCompilationUnit(firstToken);