RFR: 8282191: Implementation of Foreign Function & Memory API (Preview) [v5]

[Maurizio Cimadamore]

> This PR contains the API and implementation changes for JEP-424 [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/424

Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:

  Drop redundant javadoc statements re. handling of nulls
  (handling of nulls is specified once and for all in the package javadoc)

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7888/files
  - new: https://git.openjdk.java.net/jdk/pull/7888/files/7ec71f73..c9bc9a70

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7888&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7888&range=03-04

  Stats: 12 lines in 2 files changed: 3 ins; 8 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7888.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7888/head:pull/7888

PR: https://git.openjdk.java.net/jdk/pull/7888