Move Extension into extensions namespace

chrome/browser/extensions/external_registry_extension_loader_win.cc

 // Copyright (c) 2011 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/external_registry_extension_loader_win.h"
 
 #include "base/bind.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/memory/scoped_handle.h"
@@ skipping 102 matching lines @@
     if (key.ReadValue(kRegistryExtensionVersion, &extension_version)
         != ERROR_SUCCESS) {
       // TODO(erikkay): find a way to get this into about:extensions
       LOG(ERROR) << "Missing value " << kRegistryExtensionVersion
                  << " for key " << key_path << ".";
       continue;
     }
 
     std::string id = WideToASCII(*it);
     StringToLowerASCII(&id);
-    if (!Extension::IdIsValid(id)) {
+    if (!extensions::Extension::IdIsValid(id)) {
       LOG(ERROR) << "Invalid id value " << id
                  << " for key " << key_path << ".";
       continue;
     }
 
     scoped_ptr<Version> version;
     version.reset(Version::GetVersionFromString(
                       WideToASCII(extension_version)));
     if (!version.get()) {
       LOG(ERROR) << "Invalid version value " << extension_version
                  << " for key " << key_path << ".";
       continue;
     }
 
     prefs->SetString(
         id + "." + ExternalExtensionProviderImpl::kExternalVersion,
         WideToASCII(extension_version));
     prefs->SetString(
         id + "." + ExternalExtensionProviderImpl::kExternalCrx,
         extension_path_str);
   }
 
   prefs_.reset(prefs.release());
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&ExternalRegistryExtensionLoader::LoadFinished, this));
 }