RFR: 8290333: Remove os_share_*.hpp [v2]

[Ioi Lam]

> Please remove this trivial change. Although many files are changed, I am only removing unused files and changing a couple of comments.

Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:

  improved comments

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9506/files
  - new: https://git.openjdk.org/jdk/pull/9506/files/5cbaff2d..85376c2a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9506&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9506&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/9506.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9506/head:pull/9506

PR: https://git.openjdk.org/jdk/pull/9506