[Buildbot] #2574: GerritChangeSource extracts wrong branch name when using Gerrit 2.7

[Buildbot trac]

#2574: GerritChangeSource extracts wrong branch name when using Gerrit 2.7
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Reporter:  dluntzer          |       Owner:
    Type:  defect            |      Status:  assigned
Priority:  patches-accepted  |   Milestone:  0.9.+
 Version:  0.8.8             |  Resolution:
Keywords:  gerrit            |
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Comment (by RockHed):

 We just hit something related to this when a patchset got rebased. It
 looks like there were two events:
 2016-03-09 17:23:28-0800 [-] gerrit:
 {"uploader":{"name":"gerrit","email":"wgerrit at ourcompany","username":"wgerrit"},"patchSet":{"number":"2","revision":"291d7a53d276da369b38f2fbb8292b88847ae6c1","parents":["4f1d340969e3b3c4b0acfc02bc8bdb03eb1d4014"],"ref":"refs/changes/69/4269/2","uploader":{"name":"
 Gerrit","email":"wgerrit at ourcompany","username":"wgerrit"},"createdOn":1457573007,"author":{"name":"Some
 User","email":"someuser at ourcompany","username":"someuser"},"isDraft":false,"kind":"TRIVIAL_REBASE","
 sizeInsertions":14,"sizeDeletions":-17},"change":{"project":"Project1","branch":"master","id":"Iaf1e6bc230cc1538c490898f7dc984c879798930","number":"4269","subject":"some
 subject","owner":{"name":"Some
 User","email":"someuser at ourcompany","username":"someuser"},"url":"https://gerrit.ourcompany/4269","commitMessage":"some
 subject\nChange-Id: Iaf1e6
 bc230cc1538c490898f7dc984c879798930\n","status":"NEW"},"type":"patchset-
 created","eventCreatedOn":1457573007}
 2016-03-09 17:23:28-0800 [-] added change
 Change(revision=u'291d7a53d276da369b38f2fbb8292b88847ae6c1', who=u'Some
 User <someuser at ourcompany>', branch=u'master/4269', comments=u'some
 subject.', when=1457573008, category=u'patchset-created', project=
 Project1', repository=u'ssh://wgerrit@gerrit.company:29418/Project1',
 codebase=u'') to database

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Ticket URL: <http://trac.buildbot.net/ticket/2574#comment:8>
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