RFR: 8260019: Move some Thread subtypes out of thread.hpp [v2]

[Ioi Lam]

> thread.hpp is 2133 lines long and is included by about 800 out of 1000 HotSpot .o files. It also pulls in many other header files.
> 
> Many of the Thread subtypes are infrequently used. This RFE move the easy ones to compilerThread.hpp and nonJavaThread.hpp. This reduces thread.hpp to 1888 lines.
> 
> (I hope to do more refactoring of thread.hpp in future RFEs).
> 
> Tested with mach5: tier1, builds-tier2, builds-tier3, builds-tier4 and builds-tier5. Also locally: aarch64, arm, ppc64, s390, x86, and zero.

Ioi Lam has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains four commits:

 - fixed merge
 - Merge branch 'master' into 8260019-move-some-subtypes-out-of-thread-hpp
 - fixed copyright year
 - 8260019: Move some Thread subtypes out of thread.hpp

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

Changes: https://git.openjdk.java.net/jdk/pull/2390/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2390&range=01
  Stats: 1392 lines in 19 files changed: 762 ins; 620 del; 10 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2390.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2390/head:pull/2390

PR: https://git.openjdk.java.net/jdk/pull/2390