Control zero suggest with a pref, not a switch.

chrome/browser/prefs/browser_prefs.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/prefs/browser_prefs.h"
 
 #include "chrome/browser/about_flags.h"
 #include "chrome/browser/accessibility/invert_bubble_prefs.h"
+#include "chrome/browser/autocomplete/zero_suggest_provider.h"
 #include "chrome/browser/autofill/autofill_manager.h"
 #include "chrome/browser/background/background_mode_manager.h"
 #include "chrome/browser/bookmarks/bookmark_utils.h"
 #include "chrome/browser/browser_shutdown.h"
 #include "chrome/browser/chrome_content_browser_client.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
 #include "chrome/browser/debugger/devtools_window.h"
 #include "chrome/browser/download/download_prefs.h"
 #include "chrome/browser/extensions/api/commands/command_service.h"
@@ skipping 197 matching lines @@
   PrefProxyConfigTrackerImpl::RegisterPrefs(user_prefs);
   PrefsTabHelper::RegisterUserPrefs(user_prefs);
   ProfileImpl::RegisterUserPrefs(user_prefs);
   PromoResourceService::RegisterUserPrefs(user_prefs);
   ProtocolHandlerRegistry::RegisterPrefs(user_prefs);
   RegisterBrowserUserPrefs(user_prefs);
   SessionStartupPref::RegisterUserPrefs(user_prefs);
   TemplateURLPrepopulateData::RegisterUserPrefs(user_prefs);
   TranslatePrefs::RegisterUserPrefs(user_prefs);
   web_intents::RegisterUserPrefs(user_prefs);
+  ZeroSuggestProvider::RegisterUserPrefs(user_prefs);
 
 #if defined(ENABLE_CONFIGURATION_POLICY)
   policy::URLBlacklistManager::RegisterPrefs(user_prefs);
 #endif
 
 #if defined(TOOLKIT_VIEWS)
   RegisterInvertBubbleUserPrefs(user_prefs);
 #elif defined(TOOLKIT_GTK)
   BrowserWindowGtk::RegisterUserPrefs(user_prefs);
 #endif
@@ skipping 99 matching lines @@
     }
     local_state->ClearPref(prefs::kLastPromptedGoogleURL);
 
     current_version |= GOOGLE_URL_TRACKER_PREFS;
     local_state->SetInteger(prefs::kMultipleProfilePrefMigration,
                             current_version);
   }
 }
 
 }  // namespace chrome