RFR: 8276548: Use range based visitor for Howl-Full cards [v2]

[Thomas Schatzl]

> Hi all,
> 
>   can I have reviews for this change that improves the way G1 iterates over Howl-Full containers (i.e. "Full" cardsetptrs within a Howl cardset container)? Instead of calling the visitor method `do_card` to mark a single card for all cards in the range, just call the range-based visitor method `do_card_range`. This is also a little bit more efficient.
> 
> This change is a requirement for [JDK-8275056](https://bugs.openjdk.java.net/browse/JDK-8275056).
> 
> Testing: tier1-5
> 
> Thanks,
>   Thomas

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

  Improve chunk marking

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6230/files
  - new: https://git.openjdk.java.net/jdk/pull/6230/files/a51ec682..f78e74b6

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6230&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6230&range=00-01

  Stats: 5 lines in 1 file changed: 2 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6230.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6230/head:pull/6230

PR: https://git.openjdk.java.net/jdk/pull/6230