RFR (JAXP) 8152912: SAX XMLReaderFactory needs to be ServiceLoader compliant

[huizhe wang]

Hi,

Please review a change that adds a step using the ServiceLoader to 
XMLReaderFactory's provider-lookup process. Meanwhile, XMLReaderFactory 
is deprecated in favor of javax.xml.parsers.SAXParserFactory.

JBS: https://bugs.openjdk.java.net/browse/JDK-8152912
Webrev: http://cr.openjdk.java.net/~joehw/jdk9/8152912/webrev/

The change has been verified by SQE test that Frank will submit soon for 
review (that is, when he starts to work at his local time).

Thanks,
Joe