Add the c++ code part of bindings2/

sky/engine/bindings2/builtin_sky.h

Index: sky/engine/bindings2/builtin_sky.h
diff --git a/sky/engine/bindings2/builtin_sky.h b/sky/engine/bindings2/builtin_sky.h
new file mode 100644
index 0000000000000000000000000000000000000000..04bf57258fb391e74cc1874e5190982200c1b593
--- /dev/null
+++ b/sky/engine/bindings2/builtin_sky.h
@@ -0,0 +1,34 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SKY_ENGINE_BINDINGS2_BUILTIN_SKY_H_
+#define SKY_ENGINE_BINDINGS2_BUILTIN_SKY_H_
+
+#include "base/macros.h"
+#include "dart/runtime/include/dart_api.h"
+#include "sky/engine/tonic/dart_class_provider.h"
+#include "sky/engine/tonic/dart_persistent_value.h"
+
+namespace blink {
+class DOMDartState;
+
+class BuiltinSky : public DartClassProvider {
+ public:
+  explicit BuiltinSky(DOMDartState* dart_state);
+  ~BuiltinSky();
+
+  void InstallWindow(DOMDartState* dart_state);
+
+  // DartClassProvider:
+  Dart_Handle GetClassByName(const char* class_name) override;
+
+ private:
+  DartPersistentValue library_;
+
+  DISALLOW_COPY_AND_ASSIGN(BuiltinSky);
+};
+
+}  // namespace blink
+
+#endif  // SKY_ENGINE_BINDINGS2_BUILTIN_SKY_H_