RFR: 8332181: Deprecate for removal the MulticastSocket.send(DatagramPacket, byte) and setTTL/getTTL methods on DatagramSocketImpl and MulticastSocket [v3]

[Jaikiran Pai]

> Can I please get a review of this change which proposes to deprecate for removal 3 methods on `java.net.MulticastSocket`? This addresses https://bugs.openjdk.org/browse/JDK-8332181.
> 
> As noted in that issue these methods have been deprecated since Java 1.2 and 1.4 days. They currently have replacement methods (noted in their javadoc) which have been in use for several releases. This commit updates these deprecated methods to deprecated for removal, to allow for their removal in a future release.
> 
> No new tests have been added and existing tests in tier1, tier2 and tier3 continue to pass.

Jaikiran Pai 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 five additional commits since the last revision:

 - merge latest from master branch
 - also deprecate for removal DatagramSocketImpl.getTTL()/setTTL()
 - also add forRemoval in internal classes
 - add "since" for the deprecation
 - 8332181: Deprecate for removal the java.net.MulticastSocket.setTTL/getTTL and the 2-arg send methods

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/19242/files
  - new: https://git.openjdk.org/jdk/pull/19242/files/6cece088..9fe4f2f6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19242&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19242&range=01-02

  Stats: 41541 lines in 558 files changed: 34423 ins; 5119 del; 1999 mod
  Patch: https://git.openjdk.org/jdk/pull/19242.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19242/head:pull/19242

PR: https://git.openjdk.org/jdk/pull/19242