[jdk16] RFR: 8259025: Record compact constructor using Objects.requireNonNull

[Vicente Romero]

Hi,

This PR is basically a backport to 16 of the code already reviewed at [PR-1917](https://github.com/openjdk/jdk/pull/1917).

TIA

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

Commit messages:
 - 8259025: Record compact constructor using Objects.requireNonNull

Changes: https://git.openjdk.java.net/jdk16/pull/133/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16&pr=133&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8259025
  Stats: 15 lines in 2 files changed: 11 ins; 1 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk16/pull/133.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16 pull/133/head:pull/133

PR: https://git.openjdk.java.net/jdk16/pull/133