RFR: 8282978: Wrong parameter passed to GetStringXXXChars in various places

[Zhengyu Gu]

Another trivial cleanup to fix the last parameter of `GetStringXXXChars` calls, should be a `jboolean*` instead of a `jboolean`.

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Commit messages:
 - Fix
 - 8282978: Wrong parameter passed to GetStringXXXChars in various places

Changes: https://git.openjdk.java.net/jdk/pull/7779/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7779&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8282978
  Stats: 22 lines in 9 files changed: 0 ins; 0 del; 22 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7779.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7779/head:pull/7779

PR: https://git.openjdk.java.net/jdk/pull/7779