[jdk21u-dev] RFR: 8313882: Fix -Wconversion warnings in runtime code

[Aleksey Shipilev]

Unclean backport to provide cleaner ground for future backports.

There were two minor conflicts in `attachListener.cpp` and `globals.hpp`.

Additional testing:
 - [x] Linux x86_64 server fastdebug, `all`

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Commit messages:
 - Merge branch 'master' into JDK-8313882-fix-wconversion-runtime
 - Backport f47767ffef29c777e2da0262fa3299564d59f461

Changes: https://git.openjdk.org/jdk21u-dev/pull/788/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=788&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313882
  Stats: 138 lines in 26 files changed: 3 ins; 9 del; 126 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/788.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/788/head:pull/788

PR: https://git.openjdk.org/jdk21u-dev/pull/788