Extend EventFilter to handle the case where EventMatchers from event X get

chrome/common/extensions/event_matcher.cc

 // 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_matcher.h"
 #include "chrome/common/extensions/event_filtering_info.h"
 
+namespace {
+const char kUrlFiltersKey[] = "url";
+}
+
 namespace extensions {
 
-EventMatcher::EventMatcher() {
+EventMatcher::EventMatcher(scoped_ptr<base::DictionaryValue> filter)
+    : filter_(filter.Pass()) {
 }
 
 EventMatcher::~EventMatcher() {
 }
 
 bool EventMatcher::MatchNonURLCriteria(
     const EventFilteringInfo& event_info) const {
   // There is currently no criteria apart from URL criteria.
   return true;
 }
 
+int EventMatcher::GetURLFilterCount() const {
+  base::ListValue* url_filters = NULL;
+  if (filter_->GetList(kUrlFiltersKey, &url_filters))
+    return url_filters->GetSize();
+  return 0;
+}
+
+bool EventMatcher::GetURLFilter(int i, base::DictionaryValue** url_filter_out) {
+  base::ListValue* url_filters = NULL;
+  if (filter_->GetList(kUrlFiltersKey, &url_filters)) {
+    return url_filters->GetDictionary(i, url_filter_out);
+  }
+  return false;
+}
+
+int EventMatcher::HasURLFilters() const {
+  return GetURLFilterCount() != 0;
+}
+
 }  // namespace extensions