RFR: 8266017: Refactor the *klass::array_klass_impl code to separate the non-exception-throwing API [v3]

[David Holmes]

> We currently have array_klass() and array_klass_or_null(), where the former can throw exceptions and the latter can not. But they both delegate to:
> 
> array_klass_impl(bool or_null, TRAPS)
> 
> which combines both the exception-throwing and non-exception-throwing code into one method declared with TRAPS. To make progress with the change of TRAPS to JavaThread (JDK-8252685) we need to separate these code paths into distinct methods.
> 
> Testing: tiers 1-3 (in progress)
> 
> Thanks,
> David

David Holmes has updated the pull request incrementally with one additional commit since the last revision:

  Updated comment and simplify code structure in one method

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3711/files
  - new: https://git.openjdk.java.net/jdk/pull/3711/files/80c307c0..d7e7d5a4

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3711&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3711&range=01-02

  Stats: 8 lines in 1 file changed: 3 ins; 3 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3711.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3711/head:pull/3711

PR: https://git.openjdk.java.net/jdk/pull/3711