Make extensions DSE persistent in browser prefs

chrome/browser/search_engines/chrome_template_url_service_client.cc

 // Copyright 2014 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/search_engines/chrome_template_url_service_client.h"
 
 #include "base/memory/ptr_util.h"
 #include "components/history/core/browser/history_service.h"
+#include "components/search_engines/default_search_manager.h"
 #include "components/search_engines/template_url_service.h"
+#include "extensions/browser/extension_pref_value_map.h"
 #include "extensions/common/constants.h"
 
 ChromeTemplateURLServiceClient::ChromeTemplateURLServiceClient(
-    history::HistoryService* history_service)
+    history::HistoryService* history_service,
+    ExtensionPrefValueMap* extension_prefs_value_map)
     : owner_(NULL),
       history_service_observer_(this),
-      history_service_(history_service) {
+      history_service_(history_service),
+      extension_prefs_value_map_(extension_prefs_value_map) {
   // TODO(sky): bug 1166191. The keywords should be moved into the history
   // db, which will mean we no longer need this notification and the history
   // backend can handle automatically adding the search terms as the user
   // navigates.
   if (history_service_)
     history_service_observer_.Add(history_service_);
 }
 
 ChromeTemplateURLServiceClient::~ChromeTemplateURLServiceClient() {
 }
@@ skipping 34 matching lines @@
                               history::RedirectList(),
                               ui::PAGE_TRANSITION_KEYWORD_GENERATED,
                               history::SOURCE_BROWSED, false);
 }
 
 bool ChromeTemplateURLServiceClient::IsOmniboxExtensionURL(
     const std::string& url) {
   return GURL(url).SchemeIs(extensions::kExtensionScheme);
 }
 
+std::string ChromeTemplateURLServiceClient::GetExtensionControllingDSEPref() {
+  if (!extension_prefs_value_map_)
+    return std::string();  // Can be null during testing.
+  return extension_prefs_value_map_->GetExtensionControllingPref(
+      DefaultSearchManager::kDefaultSearchProviderDataPrefName);
+}
+
 void ChromeTemplateURLServiceClient::OnURLVisited(
     history::HistoryService* history_service,
     ui::PageTransition transition,
     const history::URLRow& row,
     const history::RedirectList& redirects,
     base::Time visit_time) {
   DCHECK_EQ(history_service_, history_service);
   if (!owner_)
     return;
 
   TemplateURLService::URLVisitedDetails visited_details;
   visited_details.url = row.url();
   visited_details.is_keyword_transition =
       ui::PageTransitionCoreTypeIs(transition, ui::PAGE_TRANSITION_KEYWORD);
   owner_->OnHistoryURLVisited(visited_details);
 }