Avoids creating unversioned file test/0/build.xml.

* [JENKINS-43653] - Ensure AbstractItem#delete() NPE and RTE safety when checking executors.

This change adds missing NPE checks and also improves handling of Executables#getParentOf(), which may throw undocumented Runtime exceptions if Executable uses core API below 1.377 and does not implement getParent(). Executor#stop() has been also modified to explicitly handle the issue though there is still the same issue with estimated execution times.

* [JENKINS-43653] - Address comments from @jglick, restrict newly introduced API

* [JENKINS-43653] - Address comments from @stephenc

* [JENKINS-43653] - Cleanup "unrelevant" changes to make @stephenc and @jglick happy

* [JENKINS-43653] - Cleanup the leftover

* [JENKINS-43653] - Drop the changes in Executables

Fix Javadoc generation error due to incomplete class reference

[JENKINS-42717] - Prevent NPE when a non-existent Default View is specified in the global config (#2815)

* [JENKINS-42717] - Document view management methods in Jenkins and ViewGroupMixIn

* [KENKINS-42717] - GlobalDefauldViewConfiguration should not fail with NPE when the view is missing

* [JENKINS-42717] - Draft the direct unit test

* [JENKINS-42717] - Fix the tes implementation

* [JENKINS-42717] - Make FormException localizable

* [JENKINS-42717] - Fix te build glitch

[JENKINS-43531] Plugins may not be expecting InvalidPathException

* [JENKINS-42861] - Properly deprecate the HudsonExceptionNote implementation

It is a replacement of the original fix in https://github.com/jenkinsci/jenkins/pull/2808.

The implementation provides deprecates the annotation of the new stacktraces, but it retains the binary and the persisted data compatibility, which were missing in the original PR.
In the longer-term the hyperlinks should be replaced by the best possible equivalent (JIRA search, grepcode or whatever).

* [JENKINS-42861] - Cleanup the deprecated functionality

Deleted rc.changelog.rb

[JENKINS-21695] - The CompressionFilter.uncaughtExceptionHandler must not attempt to write to a committed response. (#2834)

- Plugins should really be expecting it, but as historically they have not, may as well convert to IOE for them

Also allows us to revert ce5c5174 and thus reapply 416fdddb.

This reverts commit 416fdddb.

[FIX JENKINS-41778] - setup wizard issues when failures