RFR: 8266496: WBIsKlassAliveClosure.do_klass() fails for hidden classes [v2]

[Harold Seigel]

> Please review this small fix for JDK-8266496.  The fix changes WBIsKlassAliveClosure.do_klass() so that when it compares the specified name with the name of a hidden class, it truncates the hidden class's name at the first '+' character before doing the comparison.  This should work except in the rare case when the pre-mangled hidden class name contains a '+' character.
> 
> The fix was tested with Mach5 tiers 1 and 2 on Linux, Mac OS, and Windows, and tiers 3-5 on Linux x64.
> 
> Thanks, Harold

Harold Seigel has updated the pull request incrementally with one additional commit since the last revision:

  Update test

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3882/files
  - new: https://git.openjdk.java.net/jdk/pull/3882/files/c5e96925..36739c57

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3882&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3882&range=00-01

  Stats: 45 lines in 1 file changed: 9 ins; 24 del; 12 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3882.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3882/head:pull/3882

PR: https://git.openjdk.java.net/jdk/pull/3882