Bug 1345980 - Mark up all taskcluster mochitest jobs with tag 'test-type: mochitest' r=dustin

Necessary for treeherder action retriggering code to recognize them as supporting
this action.

MozReview-Commit-ID: BY6OCUFsYlK

--HG--
extra : rebase_source : 6cc4bc8b1cfde29f793fd910bf99f8d3e36603da

taskcluster/ci/test/tests.yml

@@ -383,8 +383,6 @@ mochitest:
             linux64-jsdcov/opt: mochitest/plain-chunked-coverage
             default: mochitest/plain-chunked
     treeherder-symbol: tc-M()
-    tags:
-        test-type: mochitest
     loopback-video: true
     instance-size:
         by-test-platform:

taskcluster/taskgraph/transforms/tests.py

@@ -369,6 +369,14 @@ def set_treeherder_machine_platform(config, tests):
         yield test
 
 
+@transforms.add
+def set_mochitest_test_type(config, tests):
+    for test in tests:
+        if type(test['suite']) == str and test['suite'].startswith('mochitest'):
+            test.setdefault('tags', {})['test-type'] = 'mochitest'
+        yield test
+
+
 @transforms.add
 def set_asan_docker_image(config, tests):
     """Set the appropriate task.extra.treeherder.docker-image"""