Signals cleanup work

[tstuefe]

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Testing

	Linux x64	Linux x86	Windows x64	macOS x64
Build	⏳ (1/5 running)	✔️ (2/2 passed)	⏳ (1/2 running)	✔️ (2/2 passed)
Test (tier1)		⏳ (4/9 running)		⏳ (7/9 running)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/982/head:pull/982
$ git checkout pull/982

[bridgekeeper]

👋 Welcome back stuefe! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@tstuefe The following label will be automatically applied to this pull request:

• hotspot

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[openjdk]

@tstuefe this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout signals-cleanup-work
git fetch https://git.openjdk.java.net/jdk master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[tstuefe]

Closed, this moved to a new branch.