startup: Put it in chrome namespace.

chrome/browser/ui/startup/default_browser_prompt_win.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/ui/startup/default_browser_prompt.h"
 
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/shell_integration.h"
 #include "chrome/browser/ui/browser.h"
@@ skipping 52 matching lines @@
   registrar_.RemoveAll();
   bool as_dialog =
       profile_->GetPrefs()->GetBoolean(prefs::kDefaultBrowserFlowDialog);
 
   SetAsDefaultBrowserUI::Show(profile_, browser, as_dialog);
   delete this;
 }
 
 }  // namespace
 
-namespace browser {
+namespace chrome {
 
 void ShowFirstRunDefaultBrowserPrompt(Profile* profile) {
   if ((ShellIntegration::IsDefaultBrowser() ==
            ShellIntegration::NOT_DEFAULT_WEB_CLIENT) &&
       (ShellIntegration::CanSetAsDefaultBrowser() ==
            ShellIntegration::SET_DEFAULT_INTERACTIVE)) {
     // If the only available mode of setting the default browser requires
     // user interaction, it means this couldn't have been done yet.
     SetMetroBrowserFlowLauncher::LaunchSoon(profile);
   }
 }
 
-}  // namespace browser
+}  // namespace chrome