RFR: 8295212: G1: Add wrapper for TruncatedSeqs that need separation by gc phase [v2]

[Thomas Schatzl]

> Hi all,
> 
>   can I have reviews for this small refactoring that wraps predictor sequences that are split across gc phases in one more convenient wrapper class to avoid some code repetition?
> 
> Testing: tier1
> 
> Thanks,
>   Thomas

Thomas Schatzl has updated the pull request incrementally with one additional commit since the last revision:

  Use correct sequence for checking mixed samples

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/10793/files
  - new: https://git.openjdk.org/jdk/pull/10793/files/f81f6d43..4969c8db

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10793&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10793&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/10793.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10793/head:pull/10793

PR: https://git.openjdk.org/jdk/pull/10793