RFR: 8305062: Refactor CardTable::resize_covered_region

Tue Mar 28 10:07:33 UTC 2023

Simple refactoring to make logic around cardtable cover-region more concrete, since #generations and gen-boundary is fixed for Serial/Parallel.

Test: tier1-6

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Commit messages:
 - card-table-clear-memregion

Changes: https://git.openjdk.org/jdk/pull/13206/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13206&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305062
  Stats: 278 lines in 8 files changed: 40 ins; 188 del; 50 mod
  Patch: https://git.openjdk.org/jdk/pull/13206.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13206/head:pull/13206

PR: https://git.openjdk.org/jdk/pull/13206