Create interface "EventPageTracker" for checking an extension's

extensions/browser/event_page_tracker.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 EXTENSIONS_BROWSER_EVENT_PAGE_TRACKER_H_
+#define EXTENSIONS_BROWSER_EVENT_PAGE_TRACKER_H_
+
+#include <string>
+
+#include "base/callback.h"
+
+namespace extensions {
+
+class Extension;
+class ExtensionHost;
+
+// Defines a set of methods that can be used to track an extension's event page
+// suspend state.
+class EventPageTracker {
+ public:
+  // Returns true if an extension's event page is active,
+  // or false if it is suspended.
+  virtual bool IsEventPageActive(const std::string& extension_id) = 0;
+
+  // Wakes an extension's event page from a suspended state and calls
+  // |callback| after it is reactivated.
+  //
+  // The callback will be passed true if the extension was

[mark a. foltz, 2015/04/27 23:26:40]

Rewrap this to 80 cols.

[Kevin M, 2015/04/28 21:12:14]

Done.

+  // woken up successfully, or false if an error occurred.
+  //
+  // Function will return true if a wake operation was scheduled successfully,
+  // or false if the event page was already active and did not require waking.
+  virtual bool WakeEventPage(const std::string& extension_id,
+                             const base::Callback<void(bool)>& callback) = 0;
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_EVENT_PAGE_TRACKER_H_