RFR: 8286397: Address possibly lossy conversions in jdk.hotspot.agent [v2]

[Ryan Ernst]

> Applied required casts in jdk.hotspot.agent for the upcoming warning.
> Verified by cherry-picking @asotona's patch.

Ryan Ernst has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge branch 'master' into implicit_casts_jdk.hotspot.agent
 - 8286397: Address possibly lossy conversions in jdk.hotspot.agent
   
   Applied required casts in jdk.hotspot.agent for the upcoming warning.
   Verified by cherry-picking @asotona's patch.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9280/files
  - new: https://git.openjdk.org/jdk/pull/9280/files/b984d3bb..fb74a60f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9280&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9280&range=00-01

  Stats: 126 lines in 16 files changed: 61 ins; 55 del; 10 mod
  Patch: https://git.openjdk.org/jdk/pull/9280.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9280/head:pull/9280

PR: https://git.openjdk.org/jdk/pull/9280