Wholesale move sky/engine/tonic to tonic

tonic/dart_dependency_catcher.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_ENGINE_TONIC_DART_DEPENDENCY_CATCHER_H_
+#define SKY_ENGINE_TONIC_DART_DEPENDENCY_CATCHER_H_
+
+#include <unordered_set>
+
+#include "base/macros.h"
+
+namespace blink {
+class DartLibraryLoader;
+
+// A base class to represent a dependency.
+class DartDependency {};
+
+// To catch the dependencies for a library, put a DartDependencyCatcher on the
+// stack during the call to Dart_LoadLibrary.
+class DartDependencyCatcher {
+ public:
+  explicit DartDependencyCatcher(DartLibraryLoader& loader);
+  ~DartDependencyCatcher();
+
+  void AddDependency(DartDependency* dependency);
+  const std::unordered_set<DartDependency*>& dependencies() const {
+    return dependencies_;
+  }
+
+ private:
+  DartLibraryLoader& loader_;
+  std::unordered_set<DartDependency*> dependencies_;
+
+  DISALLOW_COPY_AND_ASSIGN(DartDependencyCatcher);
+};
+
+}  // namespace blink
+
+#endif  // SKY_ENGINE_TONIC_DART_DEPENDENCY_CATCHER_H_