Run on CI.

Author: matanlurey

testing/run_tests.py

@@ -922,6 +922,7 @@ def build_dart_host_test_list(build_dir):
               os.path.join(build_dir, 'dart-sdk', 'lib', 'libraries.json'),
           ],
       ),
+      (os.path.join('flutter', 'tools', 'dir_contents_diff'), []),
       (os.path.join('flutter', 'tools', 'engine_tool'), []),
       (os.path.join('flutter', 'tools', 'githooks'), []),
       (os.path.join('flutter', 'tools', 'header_guard_check'), []),

tools/dir_contents_diff/pubspec.yaml

@@ -3,6 +3,7 @@ environment:
   sdk: '>=3.2.0-0 <4.0.0'
 dev_dependencies:
   litetest: any
+  path: any
 dependency_overrides:
   async_helper:
     path: ../../../third_party/dart/pkg/async_helper