Introduce sky_packager

sky/tools/packager/scope.h

+// Copyright 2015 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_TOOLS_PACKAGER_SCOPE_H_
+#define SKY_TOOLS_PACKAGER_SCOPE_H_
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "dart/runtime/include/dart_api.h"
+
+class DartIsolateScope {
+ public:
+  explicit DartIsolateScope(Dart_Isolate isolate) {
+    CHECK(!Dart_CurrentIsolate());
+    Dart_EnterIsolate(isolate);
+  }
+  ~DartIsolateScope() { Dart_ExitIsolate(); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DartIsolateScope);
+};
+
+class DartApiScope {
+ public:
+  DartApiScope() { Dart_EnterScope(); }
+  ~DartApiScope() { Dart_ExitScope(); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DartApiScope);
+};
+
+#endif  // SKY_TOOLS_PACKAGER_SCOPE_H_