Add common code for extensions event filtering.

chrome/common/extensions/event_filtering_info.h

Index: chrome/common/extensions/event_filtering_info.h
diff --git a/chrome/common/extensions/event_filtering_info.h b/chrome/common/extensions/event_filtering_info.h
new file mode 100644
index 0000000000000000000000000000000000000000..83ef1f2d0d2234fdd4dd9f57714f153f1bc15ef3
--- /dev/null
+++ b/chrome/common/extensions/event_filtering_info.h
@@ -0,0 +1,36 @@
+// Copyright (c) 2012 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 CHROME_COMMON_EXTENSIONS_EVENT_FILTERING_INFO_H_
+#define CHROME_COMMON_EXTENSIONS_EVENT_FILTERING_INFO_H_
+#pragma once
+
+#include "googleurl/src/gurl.h"
+
+namespace extensions {
+
+// Extra information about an event that is used in event filtering.
+//
+// This is the information that is matched against criteria specified in JS
+// extension event listeners. Eg:
+//
+// chrome.someApi.onSomeEvent.addListener(cb,
+//                                        {url: [{hostSuffix: 'google.com'}],
+//                                         tabId: 1});
+class EventFilteringInfo {
+ public:
+  EventFilteringInfo();

[Matt Perry, 2012/05/15 20:42:59]

any complex class should define an empty destructor in the .cc file. otherwise
an inline default one will be generated for every compilation unit.

[koz (OOO until 15th September), 2012/05/16 00:14:00]

Done.

+  void SetURL(const GURL& url);
+
+  bool has_url() const { return has_url_; }
+  const GURL& url() const { return url_; }
+
+ private:
+  bool has_url_;

[battre, 2012/05/15 13:12:32]

optional: could you use GURL::is_empty()?

[koz (OOO until 15th September), 2012/05/16 00:14:00]

Better to be explicit, I think.

+  GURL url_;

[battre, 2012/05/15 13:12:32]

DISALLOW_COPY_AND_ASSIGN

[koz (OOO until 15th September), 2012/05/16 00:14:00]

Done.

+};
+
+}  // namespace extensions
+
+#endif  // CHROME_COMMON_EXTENSIONS_EVENT_FILTERING_INFO_H_