Permissions: glue between Mojo and Blink for permission observing.

content/child/permissions/permission_observers_registry.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 CONTENT_CHILD_PERMISSIONS_PERMISSION_OBSERVERS_REGISTRY_H_
+#define CONTENT_CHILD_PERMISSIONS_PERMISSION_OBSERVERS_REGISTRY_H_
+
+#include <set>
+
+namespace blink {
+class WebPermissionObserver;
+}
+
+namespace content {
+
+// PermissionObserversRegistry keeps a list of WebPermissionObserver with basic
+// methods to add/removed/check. It is being used by PermissionDispatcher and
+// PermissionDispatcherThreadProxy.
+// This is not thread-safe.
+class PermissionObserversRegistry {
+ public:
+  PermissionObserversRegistry();
+  ~PermissionObserversRegistry();
+
+  void RegisterObserver(blink::WebPermissionObserver* observer);
+  void UnregisterObserver(blink::WebPermissionObserver* observer);
+  bool IsObserverRegistered(blink::WebPermissionObserver* observer) const;
+
+ private:
+  std::set<blink::WebPermissionObserver*> observers_;
+};
+
+}  // namespace content
+
+#endif // CONTENT_CHILD_PERMISSIONS_PERMISSION_OBSERVERS_REGISTRY_H_