RFR: 8332586: Avoid cloning empty arrays in java.lang.reflect.{Method,Constructor}

[jengebr]

Improve `java/lang/reflect/Method.java`  by eliminating needless cloning of Class[0] instances.  This cloning is intended to prevent callers from changing array contents, but smany Methods have zero exceptions or zero parameters, and returning the original `Class[0]` is sufficient.

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Commit messages:
 - Merge branch 'openjdk:master' into Method_ArrayCloning
 - Updating copyright year
 - Merge branch 'openjdk:master' into Method_ArrayCloning
 - Merge branch 'openjdk:master' into Method_ArrayCloning
 - Reverting to expressions rather than utility method
 - Moving utility method to AccessibleObject
 - Fixing whitespace
 - Extracted logic to utility method
 - Expanding no-cloning coverage to Constructor
 - Reducing array allocation rate by eliminating cloned Class[0]

Changes: https://git.openjdk.org/jdk/pull/19327/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19327&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8332586
  Stats: 7 lines in 2 files changed: 0 ins; 1 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/19327.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19327/head:pull/19327

PR: https://git.openjdk.org/jdk/pull/19327