[JENKINS-36732] Timestamps in Build History widget (BuildTimelineWidget) is wrong #17344

Consider a following build: (Added comments)

<?xml version='1.0' encoding='UTF-8'?>
<build>
  <actions>
    <hudson.model.CauseAction>
      <causeBag class="linked-hash-map">
        <entry>
          <hudson.model.Cause_-UserIdCause>
            <userId>admin</userId>
          </hudson.model.Cause_-UserIdCause>
          <int>1</int>
        </entry>
      </causeBag>
    </hudson.model.CauseAction>
  </actions>
  <queueId>1</queueId>
  <timestamp>1468630800000</timestamp> <!--2016-07-16 10:00:00+0900-->
  <startTime>1468634400000</startTime> <!--2016-07-16 11:00:00+0900-->
  <result>SUCCESS</result>
  <duration>1800000</duration> <!--30minutes, and finished at 2016-07-16 11:30:00+0900-->
  <charset>windows-31j</charset>
  <keepLog>false</keepLog>
  <builtOn></builtOn>
  <workspace>C:\Users\ikedam\.jenkins\workspace\test</workspace>
  <hudsonVersion>2.13</hudsonVersion>
  <scm class="hudson.scm.NullChangeLogParser"/>
  <culprits class="com.google.common.collect.EmptyImmutableSortedSet"/>
</build>


This means:

	
Scheduled at 2016-07-16 10:00:00+0900
	
Started at 2016-07-16 11:00:00+0900
	
Finished at 2016-07-16 11:30:00+0900

for this build, `BuildTimelineWidget` in the build history page displays a build  as
"Sta, 16 Jul 2016 10:00:00 - Sat, 16 Jul 2016 10:30:00", which is completely wrong.