Add common code for extensions event filtering.

chrome/common/extensions/event_matcher.h

+// 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_MATCHER_H_
+#define CHROME_COMMON_EXTENSIONS_EVENT_MATCHER_H_
+#pragma once
+
+#include "base/compiler_specific.h"

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

not necessary

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

Done.

+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+#include "chrome/common/extensions/event_filtering_info.h"

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

forward declaration?

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

Done.

+
+namespace extensions {
+
+// Matches EventFilteringInfos against a set of criteria. This is intended to
+// be used by EventRouter which performs efficient URL matching across
+// potentially many EventMatchers itself. This is why this class only exposes
+// MatchNonURLCriteria() - URL matching is handled by EventRouter.
+class EventMatcher {
+ public:
+  EventMatcher();
+  virtual ~EventMatcher();

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

why virtual?

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

Ah, cheers. Done. Originally I had implemented this in a more opaque fashion,
and had subclasses like AllEvents() and NoEvents(), but I realised that in order
for FilteredEventRouter to be able to match over multiple EventMatcher's URLs
simultaneously I'd have to expose the data they hold anyway, so I got rid of
them.

+
+  // Returns true if |event_info| satisfies this matcher's criteria, not taking
+  // into consideration any URL criteria.
+  bool MatchNonURLCriteria(const EventFilteringInfo& event_info) const;
+
+  void set_url_filters(scoped_ptr<base::ListValue> url_filters) {
+    url_filters_ = url_filters.Pass();
+  }
+
+  // Returns NULL if no url_filters have been specified.
+  base::ListValue* url_filters() const {
+    return url_filters_.get();
+  }
+
+ private:
+  scoped_ptr<base::ListValue> url_filters_;

[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_MATCHER_H_