Add common code for extensions event filtering.

chrome/common/extensions/event_filtering_info.cc

Index: chrome/common/extensions/event_filtering_info.cc
diff --git a/chrome/common/extensions/event_filtering_info.cc b/chrome/common/extensions/event_filtering_info.cc
new file mode 100644
index 0000000000000000000000000000000000000000..dcf78fc25da4b54cb3899de8664de6bfd0f397a3
--- /dev/null
+++ b/chrome/common/extensions/event_filtering_info.cc
@@ -0,0 +1,21 @@
+// 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.
+
+#include "chrome/common/extensions/event_filtering_info.h"
+
+namespace extensions {
+
+EventFilteringInfo::EventFilteringInfo()
+    : has_url_(false) {
+}
+
+EventFilteringInfo::~EventFilteringInfo() {
+}
+
+void EventFilteringInfo::SetURL(const GURL& url) {
+  url_ = url;
+  has_url_ = true;
+}
+
+}  // namespace extensions