RFR: [jdk11] 8225789: Empty method parameter type should generate ClassFormatError

[Baesken, Matthias]

Hello,
   please review the jdk11 backport of  8225789 .
Do bring the patch into jdk11  I had to confirm the length check  in ClassFileParser::verify_unqualified_name because
Of changes in the stride (the check itself integrates nicely).
Additionally the class file version in /test/hotspot/jtreg/runtime/classFileParserBug/EmptyUnqName.jasm
was adjusted to 55.

Bug/ jdk11 webrev :

https://bugs.openjdk.java.net/browse/JDK-8225789

http://cr.openjdk.java.net/~mbaesken/webrevs/8225789_jdk11/

( jdk/jdk change is : https://hg.openjdk.java.net/jdk/jdk/rev/360f8769d3dc  )

Thanks, Matthias