Oops.

tools/testing/dart/test_suite.dart

Index: tools/testing/dart/test_suite.dart
diff --git a/tools/testing/dart/test_suite.dart b/tools/testing/dart/test_suite.dart
index 933eb437819df947c73cebcb31a8036a438baaa8..ca063a2ccb5c10dc380d0e27e67477e81daf4d1b 100644
--- a/tools/testing/dart/test_suite.dart
+++ b/tools/testing/dart/test_suite.dart
@@ -264,7 +264,7 @@ class StandardTestSuite implements TestSuite {
     // Use the specified predicate, if provided.
     if (isTestFilePredicate != null) return isTestFilePredicate(filename);
 
-    filename.endsWith("Test.dart");
+    return filename.endsWith("Test.dart");
   }
 
   bool listRecursively() => false;
@@ -385,7 +385,7 @@ class StandardTestSuite implements TestSuite {
         return;
       }
     }
-    
+
     Set<String> expectations = testExpectations.expectations(testName);
     if (configuration['report']) {
       // Tests with multiple VMOptions are counted more than once.