RFR: 8296130: G1: Remove G1YoungCollector::_target_pause_time_ms [v2]

[Albert Mingkun Yang]

> Simple change of narrowing down the scope of target-pause-time.
> 
> Test: hotspot_gc

Albert Mingkun Yang has updated the pull request incrementally with one additional commit since the last revision:

  review

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Changes:
  - all: https://git.openjdk.org/jdk/pull/10919/files
  - new: https://git.openjdk.org/jdk/pull/10919/files/12f4ceb3..f0eefe25

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10919&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10919&range=00-01

  Stats: 5 lines in 1 file changed: 0 ins; 3 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/10919.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10919/head:pull/10919

PR: https://git.openjdk.org/jdk/pull/10919