The original fix was made in 0c3d6709.
In this fix, I'm also moving the code that creates LeftItem.

It makes no sense that there's Item.cancel(Queue) and Queue.cancel(Item)
and they do different things!

In particular, this includes pull request #39 from Matt that handles
'$class'

Change the javadoc of UpstreamCause to be more accurate...

there is no such mothod getFullDisplayName in a TestObject - only getDisplayName

Change-Id: Idd454be00a22ee3c93f661a3ee3ae322a25c271d

Observed in a test against 1.480:
… hudson.model.Executor run
SEVERE: Unexpected executor death
java.lang.NullPointerException
	at hudson.model.Computer.getNode(Computer.java:473)
	at hudson.slaves.SlaveComputer.getNode(SlaveComputer.java:177)
	at hudson.slaves.SlaveComputer.getRetentionStrategy(SlaveComputer.java:609)
	at hudson.slaves.SlaveComputer.taskCompleted(SlaveComputer.java:285)
	at hudson.model.queue.WorkUnitContext.synchronizeEnd(WorkUnitContext.java:140)
	at hudson.model.Executor.run(Executor.java:253)

Integrating 2.8 to really ensure SSLv2 is off (even when JDK supports
that, and we haven't found any JDKs that do that)

Signed-off-by: NOleg Nenashev <o.v.nenashev@gmail.com>

[FIXED JENKINS-19017] - FileParameter - Handle non-null file parameters as different values

Signed-off-by: NOleg Nenashev <o.v.nenashev@gmail.com>

A truly conforming servlet 3.0 container does not allow us to set "secure cookie" flag beyond ServletContextListener.onInitialized().
If we see that, don't scare the users.

Annotated hudson.model.User methods

Changed wording for command line message.

Updating javadoc after struggling to add action to nodes

- If there are any files in `$JENKINS_HOME/update-center-rootCAs` that are not ending in `.txt` and are
  not valid certificates, do not blow up the entire certificate checking (and hence the ability to see updates
  or tool installers) but rather ignore those files and warn the user that the file should not be there.
  The correct thing to do is only use as trusted certificates those certificates that parse.

- Also fix resource leak

Updating the number of provided plugins.