Rework tree APIs to reflect Google style and more const-correctness....

chrome/browser/chromeos/login/screen_locker.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/chromeos/login/screen_locker.h"
 
 #include <gdk/gdkkeysyms.h>
 #include <gdk/gdkx.h>
 #include <string>
 #include <vector>
@@ skipping 257 matching lines @@
     shutdown_button_->LayoutIn(this);
   }
 
   // ScreenLocker::ScreenLockViewContainer implementation:
   void SetScreenLockView(views::View* screen_lock_view) {
     if (screen_lock_view_) {
       RemoveChildView(screen_lock_view_);
     }
     screen_lock_view_ =  screen_lock_view;
     if (screen_lock_view_) {
-      AddChildView(0, screen_lock_view_);
+      AddChildViewAt(screen_lock_view_, 0);
     }
     Layout();
   }
 
  private:
   views::View* screen_lock_view_;
 
   chromeos::ShutdownButton* shutdown_button_;
 
   DISALLOW_COPY_AND_ASSIGN(GrabWidgetRootView);
@@ skipping 865 matching lines @@
 
 bool ScreenLocker::AcceleratorPressed(const views::Accelerator& accelerator) {
   if (!background_view_->IsScreenSaverVisible()) {
     StartScreenSaver();
     return true;
   }
   return false;
 }
 
 }  // namespace chromeos