[CodeHealth] Migrate scripts under testing/trigger_scripts to Python3

compatible syntax to permit future migration of all presubmit checks
under testing/ to Python3.

Bug: 1262363
Change-Id: Id39d1fedb106b73a5aa4e4f726e9649cc20e25a4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3472947
Reviewed-by: Mike Pinkerton <[email protected]>
Commit-Queue: Joshua Hood <[email protected]>
Cr-Commit-Position: refs/heads/main@{#976264}
diff --git a/testing/PRESUBMIT.py b/testing/PRESUBMIT.py
index 65f2d62..7ba136f 100644
--- a/testing/PRESUBMIT.py
+++ b/testing/PRESUBMIT.py
@@ -20,7 +20,10 @@
 
   output = []
   output.extend(input_api.canned_checks.RunUnitTestsInDirectory(
-      input_api, output_api, '.', [r'^.+_unittest\.py$']))
+      input_api,
+      output_api,
+      '.',
+      [r'^.+_unittest\.py$']))
   output.extend(input_api.canned_checks.RunUnitTestsInDirectory(
       input_api,
       output_api,
@@ -29,7 +32,16 @@
       [r'^.+_unittest\.py$'],
       env=testing_env))
   output.extend(input_api.canned_checks.RunPylint(
-      input_api, output_api, files_to_skip=[r'gmock.*', r'gtest.*']))
+      input_api,
+      output_api,
+      files_to_skip=[r'gmock.*', r'gtest.*', r'trigger_scripts.*']))
+  # Pylint2.7 is run on subdirs whose presubmit checks are migrated to Python3
+  output.extend(input_api.canned_checks.RunPylint(
+      input_api,
+      output_api,
+      files_to_check=[r'trigger_scripts.*\.py$'],
+      version='2.7'))
+
   return output