[9] Review request: 8028616 Htmleditorkit parser doesn't handle leading slash (/)

[dmitry markov]

Hello,

Could you review the fix for jdk9, please?
    bug: https://bugs.openjdk.java.net/browse/JDK-8028616
    webrev: http://cr.openjdk.java.net/~dmarkov/8028616/jdk9/webrev.00/

The method Parser.parseContent() should invoke legalElementContext(), if 
the parsed text is not wrapped by tags and starts with slash (/).

Thanks,
Dmitry