RFR: 8036580: CHA: improve default method support [v2]

[Vladimir Ivanov]

> Enable CHA to look for unique concrete methods under default interface methods.
> Only vtable-based implementation is affected. Old implementation is left as is.
> 
> The unit test requires #4211/#4212 to pass and relies on test code refactorings from #4213.
> 
> Testing:
> - [x] hs-tier1 - hs-tier9

Vladimir Ivanov has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase.

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4214/files
  - new: https://git.openjdk.java.net/jdk/pull/4214/files/61925b12..61925b12

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4214&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4214&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4214.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4214/head:pull/4214

PR: https://git.openjdk.java.net/jdk/pull/4214