Moved configuration of keepDependencies into AbstractProject/configure-common.jelly, since it is not a property of Fingerprinter.

Permit RunnerStack.peek to return null in case it is not in use (for example, from a workflow), so that we do not get an NPE when trying to run a task that asks for checkpoints.
https://trello.com/c/DoCMV6gB/31-runnerstack

[FIXED JENKINS-20663] For now, go back to using ZipOutputStream from Ant that supports setting the filename encoding (present in java.util.zip only in Java 7+).

Set "X-UA-Compatible" meta tag (MSIE browsers only - forces browser compatibility mode)
JS based warning if Document Mode doesn't match IE version (MSIE browsers only)

All other places use this class for a td with help icon.
This improves rendering of the different strategies under "Restrict
project naming"

Correcting change made in #1176, which introduced an NPE, to restore original logic merely wrapped in a synchronized block.
Reproduced NPE in new functional test (original bug probably very hard to reproduce).

The JNLP port is not interesting enough to warrant logging at INFO during every startup, including the vast majority of functional tests which do not even use JNLP slaves.

I think this is an oversight in bded790f. A random attacker wouldn't know the correct API token value,
so given that it matched, I think the caller should know that it was the impersonation that failed, not the authentication.

Also log this at a higher level, since this indicates a problem in SecurityRealm.

The actual implementation does not behave as nicely as one would hope, for a few reasons:
1. isEmpty actually tries to load the newestBuild, rather than simply checking whether there is some idOnDisk.
   Arguably this is necessary, since there could be an unloadable build record, in which case it would be technically correct for the map to be considered empty.
2. Loading AbstractLazyLoadRunMap.newestBuild calls search(MAX_VALUE, DESC), which behaves oddly, by doing a binary search, and thus perhaps loading lg(|map|) entries.
   You would think that it would suffice to check for the last member of idOnDisk in index.byId.
3. The iterator eagerly loads the next value before hasNext has even been called.
   Looks bad in a test, though it probably has little practical impact since most callers would be calling hasNext soon afterward anyway.
   Might cause one extra build record to be loaded unnecessarily from a limited RunList.

[JENKINS-18065] 54c08461 amendment: presumably RunMap.entrySet().iterator().next().setValue(…) should be illegal.

Now you can draw a straight vertical line and see that the logo image, the
beginning breadcrumb, and the build history are all in a straight line.

Just in case the previous fix didn't address the root cause of ZD-11985 (and given the time it takes for changes like this to land in LTS), I'm adding additional diagnostics that let us track how previous/next builds are getting discovered

Based on the last few commits, I proved that the original fix in f1430a25
doesn't really address the problem.

That is, once b2 is deleted, and after sufficient garbage collection,
we can make b2.previousBuild.get() be null, and then
b2.getPreviousBuild().getNextBuild() ends up incorrectly returning b2.

In this commit, I roll back that part of f1430a25, and then fix the
problem differently.

I started thinking that the main problem we are trying to fix here
is that the deleted build object should be unreferenceable. That is,
it should behave almost as if the object has already been GCed.
The easiest way to do this is to clear a BuildReference object,
since we always use the same BuildReference object for all inbound
references.

This change allows us to clear BuildReference. Code like
b2.getPreviousBuild() will continue to try to update
b1.nextBuildR to b2, but it will only end up wiping out the field,
only to have b1.getNextBuild() recompute the correct value.

This fix makes both test cases pass in LazyBuildMixInTest.

Undeprecating Job.getBuild, since this is the only way to look up a build by ID if you are unsure what kind of Job it is.

WARNING: Caught exception evaluating: e.hasStopPermission() in /. Reason: java.lang.NullPointerException
java.lang.NullPointerException
	at hudson.model.Executor.hasStopPermission(Executor.java:523)