Support extension precedences in declarative WebRequest API

chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry.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/browser/extensions/api/declarative_webrequest/webrequest_rules_registry.h"
 
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_condition.h"
 #include "chrome/browser/extensions/api/web_request/web_request_api_helpers.h"
+#include "chrome/browser/extensions/extension_system.h"
 #include "net/url_request/url_request.h"
 
 namespace extensions {
 
-WebRequestRulesRegistry::WebRequestRulesRegistry() {}
+WebRequestRulesRegistry::WebRequestRulesRegistry(Profile* profile) {
+  if (profile)
+    extension_info_map_ = ExtensionSystem::Get(profile)->info_map();
+}
 
 std::set<WebRequestRule::GlobalRuleId>
 WebRequestRulesRegistry::GetMatches(net::URLRequest* request,
                                     RequestStages request_stage) {
   std::set<WebRequestRule::GlobalRuleId> result;
 
   // Figure out for which rules the URL match conditions were fulfilled.
   typedef std::set<URLMatcherConditionSet::ID> URLMatches;
   URLMatches url_matches = url_matcher_.MatchURL(request->url());
 
@@ skipping 28 matching lines @@
         rule->second->CreateDeltas(request, request_stage);
     result.splice(result.begin(), rule_result);
   }
 
   return result;
 }
 
 std::string WebRequestRulesRegistry::AddRulesImpl(
     const std::string& extension_id,
     const std::vector<linked_ptr<RulesRegistry::Rule> >& rules) {
-  // TODO(battre): Retrieve this from somewhere
-  base::Time extension_installation_time;
+  base::Time extension_installation_time =
+      GetExtensionInstallationTime(extension_id);
 
   std::string error;
   RulesMap new_webrequest_rules;
 
   for (std::vector<linked_ptr<RulesRegistry::Rule> >::const_iterator rule =
        rules.begin(); rule != rules.end(); ++rule) {
     WebRequestRule::GlobalRuleId rule_id(extension_id, *(*rule)->id);
     DCHECK(webrequest_rules_.find(rule_id) == webrequest_rules_.end());
 
     scoped_ptr<WebRequestRule> webrequest_rule(
@@ skipping 94 matching lines @@
   return content::BrowserThread::IO;
 }
 
 bool WebRequestRulesRegistry::IsEmpty() const {
   return rule_triggers_.empty() && webrequest_rules_.empty() &&
       url_matcher_.IsEmpty();
 }
 
 WebRequestRulesRegistry::~WebRequestRulesRegistry() {}
 
+base::Time WebRequestRulesRegistry::GetExtensionInstallationTime(
+    const std::string& extension_id) const {
+  if (!extension_info_map_.get())  // May be NULL during testing.
+    return base::Time();
+
+  return extension_info_map_->GetInstallTime(extension_id);
+}
+
 }  // namespace extensions