Make variant based grouping conditional per project config (#2881)

Co-authored-by: Oliver Chang <oliverchang@users.noreply.github.com>

Author: Navidem

src/appengine/handlers/cron/grouper.py

@@ -19,6 +19,7 @@
 import six
 
 from clusterfuzz._internal.base import errors
+from clusterfuzz._internal.config import local_config
 from clusterfuzz._internal.crash_analysis.crash_comparer import CrashComparer
 from clusterfuzz._internal.datastore import data_handler
 from clusterfuzz._internal.datastore import data_types
@@ -127,6 +128,11 @@ def matches_top_crash(testcase, top_crashes_by_project_and_platform):
 
 def _group_testcases_based_on_variants(testcase_map):
   """Group testcases that are associated based on variant analysis."""
+  # Skip this if the project is configured so (like Google3).
+  enable = local_config.ProjectConfig().get('deduplication.variant', True)
+  if not enable:
+    return
+
   logs.log('Grouping based on variant analysis.')
   grouping_candidates = collections.defaultdict(list)
   project_num_testcases = collections.defaultdict(int)