Bug 1523303 - Align mozharness suite names with the ones in 'moztest.resolve', r=gbrown

This officially makes 'moztest.resolve' the source of truth when it comes to
suite names. It aligns that file with the names used in both the
desktop_unittest and android_emulator_unittest scripts.

Differential Revision: https://phabricator.services.mozilla.com/D27555

taskcluster/taskgraph/target_tasks.py

@@ -236,8 +236,7 @@ def target_tasks_valgrind(full_task_graph, parameters, graph_config):
         if platform not in ['linux64']:
             return False
 
-        if task.attributes.get('unittest_suite', '').startswith('mochitest') and \
-           task.attributes.get('unittest_flavor', '').startswith('valgrind-plain'):
+        if task.attributes.get('unittest_suite', '').startswith('mochitest-valgrind-plain'):
             return True
         return False