Bug 1270317 - Upgrade to Mercurial 3.7.3 in the mozharness test environment; r=jlund

We had a test environment running on Python 2.6 and an ancient version
of Mercurial. AFAICT we run Python 2.7 everywhere, so this environment
can be dropped.

We also upgrade to Mercurial 3.7.3, as that is what automation now runs.

MozReview-Commit-ID: 7WTyD3CUjtj

--HG--
extra : rebase_source : 28994488cc1ffbc779ac4f25ec0cbbd2749d169d
extra : histedit_source : bdd034b5c2d3cc479f58b614cf368372c81c8896

testing/mozharness/requirements.txt

@@ -8,7 +8,7 @@ dulwich==0.8.7
 hg-git==0.4.0
 logilab-astng==0.24.2
 logilab-common==0.59.0
-mercurial==2.6.3
+mercurial==3.7.3
 mock==1.0.1
 nose==1.2.1
 ordereddict==1.1
@@ -22,4 +22,4 @@ virtualenv==1.5.1
 wsgiref==0.1.2
 urllib3==1.9.1
 google-api-python-client==1.3.1
-oauth2client==1.4.2
+oauth2client==1.4.2

testing/mozharness/tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27-hg2.6
+envlist = py27-hg3.7
 
 [base]
 deps =
@@ -15,15 +15,10 @@ setenv =
 commands =
     coverage run --source configs,mozharness,scripts --branch {envbindir}/nosetests -v --with-xunit --rednose --force-color {posargs}
 
-[testenv:py27-hg2.6]
+[testenv:py27-hg3.7]
 deps =
     {[base]deps}
-    mercurial==2.6.2
-
-[testenv:py27-hg3.2]
-deps =
-    {[base]deps}
-    mercurial==3.2.4
+    mercurial==3.7.3
 
 [testenv:py27-coveralls]
 deps=

testing/taskcluster/tasks/tests/mozharness-gecko.yml

@@ -30,7 +30,7 @@ task:
           tc-vcs checkout ./gecko {{base_repository}} {{head_repository}} {{head_rev}} {{head_ref}} &&
           cd gecko/testing/mozharness &&
           pip install tox &&
-          tox -e py27-hg2.6 -e py27-hg3.2
+          tox -e py27-hg3.7
   extra:
     extra:
         build_product: '{{build_product}}'