RFR: 8303919: Instant.ofEpochMilli says it can throw an exception that it can't [v2]

[Eamonn McManus]

> Instant.ofEpochMilli says this:
> 
> 
> @throws DateTimeException if the instant exceeds the maximum or minimum instant
> 
> 
> But that can't happen. Even given `Long.MIN_VALUE` or `Long.MAX_VALUE` it does not throw. That's already implicitly tested in [`TestInstant`](https://github.com/openjdk/jdk/blob/a9dba565688a29bef8626488c47519008dcadbe8/test/jdk/java/time/test/java/time/TestInstant.java#L84), which calls it with both those values.

Eamonn McManus 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 two additional commits since the last revision:

 - Merge branch 'openjdk:master' into ofepochmilli
 - 8303919: Instant.ofEpochMilli javadoc bug
   
   Instant.ofEpochMilli says this:
   
   ```
   @throws DateTimeException if the instant exceeds the maximum or minimum instant
   ```
   
   But that can't happen. Even given `Long.MIN_VALUE` or `Long.MAX_VALUE`
   it does not throw. That's already implicitly tested in
   [`TestInstant`](https://github.com/openjdk/jdk/blob/a9dba565688a29bef8626488c47519008dcadbe8/test/jdk/java/time/test/java/time/TestInstant.java#L84),
   which calls it with both those values.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12958/files
  - new: https://git.openjdk.org/jdk/pull/12958/files/a902d216..4ef7b053

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12958&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12958&range=00-01

  Stats: 437214 lines in 4534 files changed: 333479 ins; 64197 del; 39538 mod
  Patch: https://git.openjdk.org/jdk/pull/12958.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/12958/head:pull/12958

PR: https://git.openjdk.org/jdk/pull/12958