Fix warnings_checker.dart handling of multitests

tests/standalone/io/platform_resolved_executable_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Process test program to test process communication.
 
 library PlatformExecutableTest;
 
 import "dart:io";
 
@@ skipping 123 matching lines @@
   // The same script is used for both running the tests and as for starting
   // child verifying the value of Platform.resolvedExecutable. If the
   // environment variable _SCRIPT_KEY is set this is a child process which
   // should print the value of Platform.resolvedExecutable.
   if (Platform.environment.containsKey(_SCRIPT_KEY)) {
     print(Platform.resolvedExecutable);
     return;
   }
 
   testDartExecShouldNotBeInCurrentDir();
-  testShouldSucceedWithSourcePlatformExecutable(); /// 00: ok
+  testShouldSucceedWithSourcePlatformExecutable(); //# 00: ok
   // dart:io does not support linking to files in Windows.
   if (!Platform.isWindows) {
-    withTempDir(testExeSymLinked); /// 01: ok
+    withTempDir(testExeSymLinked); //# 01: ok
   }
-  withTempDir(testExeDirSymLinked); /// 02: ok
-  testPathToSDKDir(); /// 03: ok
-  withTempDir(testPathPointsToSymLinkedSDKPath); /// 04: ok
+  withTempDir(testExeDirSymLinked); //# 02: ok
+  testPathToSDKDir(); //# 03: ok
+  withTempDir(testPathPointsToSymLinkedSDKPath); //# 04: ok
   // dart:io does not support linking to files in Windows.
   if (!Platform.isWindows) {
-    withTempDir(testPathToDirWithExeSymLinked); /// 05: ok
+    withTempDir(testPathToDirWithExeSymLinked); //# 05: ok
   }
-  testShouldFailOutsidePath(); /// 06: ok
+  testShouldFailOutsidePath(); //# 06: ok
 }