RFR: 8276824: refactor Thread::is_JavaThread_protected [v2]

[Daniel D.Daugherty]

> Refactor `Thread::is_JavaThread_protected(const JavaThread* p, bool checkTLHOnly)`
> into: `bool Thread::is_JavaThread_protected(const JavaThread* p)`
> and: `Thread::is_JavaThread_protected_by_TLH(const JavaThread* p)`.
> Also change callers that passed `checkTLHOnly == true` into calls to
> `Thread::is_JavaThread_protected_by_TLH(const JavaThread* p)`.
> 
> This refactoring is being tested with Mach5 Tier[1-3] (in process).
> 
> In the "Files changed" view, enable "Settings -> Hide whitespace" for an easier review.

Daniel D. Daugherty has updated the pull request incrementally with one additional commit since the last revision:

  clarify the target thread parameter.

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6315/files
  - new: https://git.openjdk.java.net/jdk/pull/6315/files/02aefa66..ea536662

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6315&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6315&range=00-01

  Stats: 17 lines in 2 files changed: 0 ins; 0 del; 17 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6315.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6315/head:pull/6315

PR: https://git.openjdk.java.net/jdk/pull/6315