[8u] RFR (S) 8211382: ISO2022JP and GB18030 NIO converter issues

[Aleksey Shipilev]

Original bug:
  https://bugs.openjdk.java.net/browse/JDK-8211382

Original fix:
  http://hg.openjdk.java.net/jdk/jdk/rev/fb71a4bc010d

The patch does not apply cleanly to 8u and needs some manual merging. Toshio and/or Ichiron, can you
please take a look, and maybe even run the tests on current 8u?

8u webrev:
  http://cr.openjdk.java.net/~shade/8211382/webrev.8u.01/

Testing: Linux x86_64 fastdebug, sun/nio/cs jtregs (failures without product fix and new tests,
passes with the complete fix)

Thanks,
-Aleksey