RFR: 8287908: Use non-cloning reflection methods where acceptable

[Сергей Цыпанов]

Instead of `Executable.getParameterTypes()` we could use `Executable.getSharedParameterTypes()` in trusted code. Same is applicable for `Executable.getExceptionTypes()`.

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Commit messages:
 - 8287908: Use non-cloning reflection methods where acceptable

Changes: https://git.openjdk.java.net/jdk/pull/9064/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=9064&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8287908
  Stats: 9 lines in 4 files changed: 0 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/9064.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/9064/head:pull/9064

PR: https://git.openjdk.java.net/jdk/pull/9064