Fix warnings_checker.dart handling of multitests

tests/language_strong/mixin_type_variable_test.dart

Index: tests/language_strong/mixin_type_variable_test.dart
diff --git a/tests/language_strong/mixin_type_variable_test.dart b/tests/language_strong/mixin_type_variable_test.dart
index 4d5c6c4bea36c28aa0269c1f2eb7a5ab8212c5f4..971b464118f4a87b626d842f2fe36ac6cc3005cd 100644
--- a/tests/language_strong/mixin_type_variable_test.dart
+++ b/tests/language_strong/mixin_type_variable_test.dart
@@ -10,23 +10,23 @@ class A<T> {
 
 class B<T> = Object with A<T>;
 
-class C<T> extends B<T> {} /// 03: ok
-class D extends B<int> {} /// 04: ok
+class C<T> extends B<T> {} //# 03: ok
+class D extends B<int> {} //# 04: ok
 
 class E = Object with A<int>;
 
-class F extends E {} /// 06: ok
+class F extends E {} //# 06: ok
 
-class G<T> extends Object with A<T> {} /// 07: ok
-class H extends Object with A<int> {} /// 08: ok
+class G<T> extends Object with A<T> {} //# 07: ok
+class H extends Object with A<int> {} //# 08: ok
 
 void main() {
-  new A<num>(); /// 01: ok
-  new B<num>(); /// 02: ok
-  new C<num>(); /// 03: continued
-  new D(); /// 04: continued
-  new E(); /// 05: ok
-  new F(); /// 06: continued
-  new G<num>(); /// 07: continued
-  new H(); /// 08: continued
+  new A<num>(); //# 01: ok
+  new B<num>(); //# 02: ok
+  new C<num>(); //# 03: continued
+  new D(); //# 04: continued
+  new E(); //# 05: ok
+  new F(); //# 06: continued
+  new G<num>(); //# 07: continued
+  new H(); //# 08: continued
 }