RFR: 8256814: WeakProcessorPhases may be redundant [v3]

[Kim Barrett]

> Please review this change which eliminates the WeakProcessorPhase class.
> 
> The OopStorageSet class is changed to provide scoped enums for the different
> categories: StrongId, WeakId, and Id (for the union of strong and weak).
> An accessor is provided for obtaining the storage corresponding to a
> category value.
> 
> Various other enumerator ranges, array sizes and indices, and iterations are
> derived directly from the corresponding OopStorageSet category's enum range.
> 
> Iteration over a category of enumerators can be done via EnumIterator.  The
> iteration over storage objects makes use of that enum iteration, rather than
> having a bespoke implementation.  Some use-cases need iteration of the
> enumerators, with storage lookup from the enumerator; other use-cases just
> need the storage objects.
> 
> Testing:
> mach5 tier1-6
> Local (linux-x64) hotspot:tier1 with -XX:+UseShenandoahGC

Kim Barrett has updated the pull request incrementally with two additional commits since the last revision:

 - update copyrights
 - remove type aliases for OopStorageSet::WeakId

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1862/files
  - new: https://git.openjdk.java.net/jdk/pull/1862/files/3a4d5b78..ebe50e35

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1862&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1862&range=01-02

  Stats: 48 lines in 17 files changed: 6 ins; 8 del; 34 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1862.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1862/head:pull/1862

PR: https://git.openjdk.java.net/jdk/pull/1862