RFR: 8335820: java/lang/invoke/LFCaching/LFSingleThreadCachingTest.java fails due to IllegalArgumentException: hash must be nonzero [v2]

[Adam Sotona]

> Class-File API constant pool implementation requires non-zero entry hash code.
> Unfortunately current implementation computes zero hash code for specific CP entries.
> 
> This patch removes invalid and obsolete `AbstractPoolEntry::phiMix` calculation and assures all pool entries have non-zero hash. A regression test of the actual zero-hash `IntegerEntry` has been added. 
> 
> All pre-computed hash codes in `BoundAttribute::standardAttribute` are updated.
> 
> The patch has no performance effect measurable by any of the actual Class-File API benchmarks.
> 
> Please review.
> 
> Thanks,
> Adam

Adam Sotona has updated the pull request incrementally with one additional commit since the last revision:

  fixed BootstrapMethodEntryImpl::computeHashCode

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/20074/files
  - new: https://git.openjdk.org/jdk/pull/20074/files/9d4a1a2a..d38b2ffb

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20074&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20074&range=00-01

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20074.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20074/head:pull/20074

PR: https://git.openjdk.org/jdk/pull/20074