Review request: 8015428: Remove unused CDS support from StringTable

[Stefan Karlsson]

http://cr.openjdk.java.net/~stefank/8015428/webrev.00/

  <http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8015428>8015428  <http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8015428>: Remove unused CDS support from StringTable
Summary: The string in StringTable is not used by CDS anymore. Remove the unnecessary code in preparation for8015422  <http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8015422>: Large performance hit when the StringTable is walked twice in Parallel Scavenge

Tested with JPRT and ad-hoc benchmark allocating and deallocating interned Strings with and without -Xshare.

thanks,
StefanK