Move tab functions off Browser into browser_tabstrip and browser_tabrestore.

chrome/browser/ui/browser_toolbar_model_delegate.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/browser_toolbar_model_delegate.h"
 
 #include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/browser_tabstrip.h"
 
 BrowserToolbarModelDelegate::BrowserToolbarModelDelegate(Browser* browser)
     : browser_(browser) {
 }
 
 BrowserToolbarModelDelegate::~BrowserToolbarModelDelegate() {
 }
 
 content::WebContents*
 BrowserToolbarModelDelegate::GetActiveWebContents() const {
-  return browser_->GetActiveWebContents();
+  return chrome::GetActiveWebContents(browser_);
 }