RFR: 8289385: Cleanup redundant synchronization in Http2ClientImpl [v2]

[Andrey Turbanov]

> Http2ClientImpl.stopping and Http2ClientImpl.failures are always accessed under synchronized(this).
> So we can remove 'volatile' modifier from 'stopping'. And remove 'synchronizedSet' wrapper from 'failures'

Andrey Turbanov has updated the pull request incrementally with one additional commit since the last revision:

  8289385: Cleanup redundant synchronization in Http2ClientImpl
  add comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/9311/files
  - new: https://git.openjdk.org/jdk/pull/9311/files/0183e96b..b38119cd

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9311&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9311&range=00-01

  Stats: 3 lines in 1 file changed: 3 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/9311.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9311/head:pull/9311

PR: https://git.openjdk.org/jdk/pull/9311