[infra] Translate _sources.gypi files to _sources.gni files

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
deleted file mode 100644
index 55d70fa6a219d765ff0e9757f7af1412bdcf728e..0000000000000000000000000000000000000000
--- a/runtime/lib/vmservice_sources.gypi
+++ /dev/null
@@ -1,11 +0,0 @@
-# Copyright (c) 2015, 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.
-
-# Sources that patch the library "dart:_vmservice".
-
-{
-  'sources': [
-    'vmservice.cc',
-  ],
-}