RFR: 8324718: Add a static function to java.util.Objects to simplify object equality checks [v6]

[David Alayachew]

> Adding a function to Objects in order to facilitate equality checking and enhance readability. You simply specify the 2 objects that you want to check for equality, and then provide the functions which will be used to provide the values that we will check for equality.

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

  Rather than reiterating the precondition, let's explain why the method failed

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Changes:
  - all: https://git.openjdk.org/jdk/pull/17603/files
  - new: https://git.openjdk.org/jdk/pull/17603/files/6d424c7a..5a578015

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17603&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17603&range=04-05

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/17603.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17603/head:pull/17603

PR: https://git.openjdk.org/jdk/pull/17603