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

runtime/bin/vmservice/vmservice_sources.gni

Index: runtime/bin/vmservice/vmservice_sources.gni
diff --git a/runtime/bin/vmservice/vmservice_sources.gypi b/runtime/bin/vmservice/vmservice_sources.gni
similarity index 62%
rename from runtime/bin/vmservice/vmservice_sources.gypi
rename to runtime/bin/vmservice/vmservice_sources.gni
index a7d06cd741659cc49dd77bfdf598e764d3d5c69c..4c5d0c6d112facafaae8b499b87796f9338b6fd2 100644
--- a/runtime/bin/vmservice/vmservice_sources.gypi
+++ b/runtime/bin/vmservice/vmservice_sources.gni
@@ -1,13 +1,11 @@
-# Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+# Copyright (c) 2017, 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.
 
 # This file contains all Dart sources for the dart:io implementation of
 # the VM Service server.
-{
-  'sources': [
-    'loader.dart',
-    'server.dart',
-    'vmservice_io.dart',
-  ],
-}
+vmservice_sources = [
+  "loader.dart",
+  "server.dart",
+  "vmservice_io.dart",
+]