Create --disable-extensions-except switch

chrome/browser/extensions/extension_service.cc

 // Copyright (c) 2013 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/extension_service.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <iterator>
@@ skipping 1428 matching lines @@
     EnableExtension(extension->id());
   }
 
   OnBlacklistUpdated();
 }
 
 void ExtensionService::AddExtension(const Extension* extension) {
   // TODO(jstritar): We may be able to get rid of this branch by overriding the
   // default extension state to DISABLED when the --disable-extensions flag
   // is set (http://crbug.com/29067).
-  if (!extensions_enabled() &&
-      !extension->is_theme() &&
+  if (!extensions_enabled() && !extension->is_theme() &&
       extension->location() != Manifest::COMPONENT &&
-      !Manifest::IsExternalLocation(extension->location())) {
+      !Manifest::IsExternalLocation(extension->location()) &&
+      !IsExtensionWhitelisted(extension->id())) {
     return;
   }
 
   bool is_extension_upgrade = false;
   bool is_extension_loaded = false;
   const Extension* old = GetInstalledExtension(extension->id());
   if (old) {
     is_extension_loaded = true;
     int version_compare_result =
         extension->version()->CompareTo(*(old->version()));
@@ skipping 1004 matching lines @@
 }
 
 void ExtensionService::OnProfileDestructionStarted() {
   ExtensionIdSet ids_to_unload = registry_->enabled_extensions().GetIDs();
   for (ExtensionIdSet::iterator it = ids_to_unload.begin();
        it != ids_to_unload.end();
        ++it) {
     UnloadExtension(*it, UnloadedExtensionInfo::REASON_PROFILE_SHUTDOWN);
   }
 }