RFR: 8264774: Implementation of Foreign Function and Memory API (Incubator) [v5]

[Maurizio Cimadamore]

> This PR contains the API and implementation changes for JEP-412 [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/412

Maurizio Cimadamore has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains ten additional commits since the last revision:

 - Merge branch 'master' into JEP-412
 - Address review comments:
   * Fix all link vs. linkplain
   * Remove `volatile` and other defensive copying in `IllegalNativeAccessChecker`
   * Added @throws clauses in restricted methods for `IllegalCallerException`
 - Address review comments:
   * fix typos in javadoc
   * document ISE being thrown in all methods accepting a scope; add more tests for that
 - Address first batch of review comments
 - Add linker test excludes for x86 and other platforms which do not support `CLinker`
 - Integrate latest API tweaks
 - Fix x86 build
 - Fix `TestLinkToNativeRBP`
 - Initial push

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3699/files
  - new: https://git.openjdk.java.net/jdk/pull/3699/files/20671853..f27db3f3

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3699&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3699&range=03-04

  Stats: 477828 lines in 3664 files changed: 4983 ins; 470775 del; 2070 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3699.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3699/head:pull/3699

PR: https://git.openjdk.java.net/jdk/pull/3699