RFR: 8275063: Implementation of Foreign Function & Memory API (Second incubator) [v6]

[Maurizio Cimadamore]

> This PR contains the API and implementation changes for JEP-419 [1]. A more detailed description of such changes, to avoid repetitions during the review process, is included as a separate comment.
> 
> [1] - https://openjdk.java.net/jeps/419

Maurizio Cimadamore has updated the pull request incrementally with two additional commits since the last revision:

 - * use `invokeWithArguments` to simplify new test
 - Add test for liveness check with high-aririty downcalls
   (make sure that if an exception occurs in a downcall because of liveness,
   ref count of other resources are left intact).

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/5907/files
  - new: https://git.openjdk.java.net/jdk/pull/5907/files/5ed94c30..a4db81fe

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=5907&range=05
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=5907&range=04-05

  Stats: 39 lines in 2 files changed: 39 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5907.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5907/head:pull/5907

PR: https://git.openjdk.java.net/jdk/pull/5907