RPR JDK-8143854: java/util/regex/RegExTest.java.RegExTest failed

[Xueming Shen]

Hi,

Please help review the change for  JDK-8143854

Issue: https://bugs.openjdk.java.net/browse/JDK-8143854
webrev: http://cr.openjdk.java.net/~sherman/8143854

This is triggered by the same cause of bug JDK-8079419. However
the fix for 8079419 missed the possibility that the last character
of the pattern might be a supplementary character, therefor the
patternLength might not be equal to pattern.length(), the check
put in fails to function.

Thanks,
Sherman