[ChromeOS] Pass optional email to auth extension.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.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/ui/webui/chromeos/login/signin_screen_handler.h"
 
 #include "base/command_line.h"
 #include "base/stringprintf.h"
 #include "base/task.h"
 #include "base/values.h"
@@ skipping 255 matching lines @@
   dns_cleared_ = true;
   ShowSigninScreenIfReady();
 }
 
 // Show sign in screen as soon as we clear dns cache the cookie jar.
 void SigninScreenHandler::ShowSigninScreenIfReady() {
   if (!dns_cleared_ || !cookies_cleared_)
     return;
 
   DictionaryValue params;
+  params.SetString("startUrl", kGaiaExtStartPage);
   params.SetString("email", email_);
 
-  std::string url = kGaiaExtStartPage;
   const std::string app_locale = g_browser_process->GetApplicationLocale();
-  if (!app_locale.empty()) {
-    url.append("?hl=");
-    url.append(app_locale);
-  }
-  params.SetString("startUrl", url);
+  if (!app_locale.empty())
+    params.SetString("hl", app_locale);
 
   params.SetBoolean("createAccount",
       UserCrosSettingsProvider::cached_allow_new_user());
   params.SetBoolean("guestSignin",
       UserCrosSettingsProvider::cached_allow_guest());
   email_.clear();
   ShowScreen(kGaiaSigninScreen, &params);
 }
 
 void SigninScreenHandler::HandleCompleteLogin(const base::ListValue* args) {
@@ skipping 163 matching lines @@
   BrowsingDataRemover* remover = new BrowsingDataRemover(
       Profile::FromBrowserContext(web_ui_->tab_contents()->browser_context()),
       BrowsingDataRemover::EVERYTHING,
       base::Time());
   remover->AddObserver(this);
   remover->Remove(BrowsingDataRemover::REMOVE_COOKIES |
                   BrowsingDataRemover::REMOVE_LSO_DATA);
 }
 
 }  // namespace chromeos