RFR: 8267834: Refactor G1CardSetAllocator and BufferNode::Allocator to use a common base class [v3]

[Ivan Walulya]

> Hi all,
> 
> Please review this change to combine free list allocation used in G1CardSetAllocator and BufferNode::Allocator into a single class. 
> 
> Testing: Tier 1-5
> 
> Thanks
> Ivan

Ivan Walulya has updated the pull request incrementally with one additional commit since the last revision:

  Kim review

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7615/files
  - new: https://git.openjdk.java.net/jdk/pull/7615/files/60d41d36..01c78d62

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7615&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7615&range=01-02

  Stats: 20 lines in 2 files changed: 6 ins; 6 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7615.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7615/head:pull/7615

PR: https://git.openjdk.java.net/jdk/pull/7615