Properly split dart:_vmservice across sdk and runtime

runtime/lib/vmservice_sources.gypi

Index: runtime/lib/vmservice_sources.gypi
diff --git a/runtime/lib/vmservice_sources.gypi b/runtime/lib/vmservice_sources.gypi
index 9fb590a6f40019d9e2717079877e855562a32a74..6eeb7596ff6f0b172d6b3a8214b556d073ddd8ab 100644
--- a/runtime/lib/vmservice_sources.gypi
+++ b/runtime/lib/vmservice_sources.gypi
@@ -2,18 +2,12 @@
 # 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.
 
-# Sources that make up the library "dart:_vmservice".
+# Sources that patch the library "dart:_vmservice".
 
 {
   'sources': [
-    'vmservice/vmservice.dart',
+    'vmservice_patch.dart',
     # The above file needs to be first as it imports required libraries.
-    'vmservice/client.dart',
-    'vmservice/constants.dart',
-    'vmservice/running_isolate.dart',
-    'vmservice/running_isolates.dart',
-    'vmservice/message.dart',
-    'vmservice/message_router.dart',
     'vmservice.cc',
   ],
 }