Move web_contents from SearchViewController to SearchTabHelper

chrome/browser/ui/search/search_tab_helper.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_SEARCH_SEARCH_TAB_HELPER_H_
 #define CHROME_BROWSER_UI_SEARCH_SEARCH_TAB_HELPER_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
+#include "chrome/browser/ui/search/search_model.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/web_contents_observer.h"
 
 class OmniboxEditModel;
 class TabContents;
 
+namespace content {
+class WebContents;
+};
+
 namespace chrome {
 namespace search {
 
-class SearchModel;
-
 // Per-tab search "helper".  Acts as the owner and controller of the tab's
 // search UI model.
 class SearchTabHelper : public content::WebContentsObserver,
                         public content::NotificationObserver {
  public:
   SearchTabHelper(TabContents* contents, bool is_search_enabled);
   virtual ~SearchTabHelper();
 
-  SearchModel* model() const {
-    return model_.get();
+  SearchModel* model() {
+    return &model_;
   }
 
+  // Lazily create web contents for NTP.  Owned by SearchTabHelper.
+  content::WebContents* GetNTPWebContents();
+
   // Invoked when the OmniboxEditModel changes state in some way that might
   // affect the search mode.
   void OmniboxEditModelChanged(OmniboxEditModel* edit_model);
 
   // content::WebContentsObserver overrides:
   virtual void NavigateToPendingEntry(
       const GURL& url,
       content::NavigationController::ReloadType reload_type) OVERRIDE;
 
   // Overridden from content::NotificationObserver:
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
  private:
   // Sets the mode of the model based on |url|.
   void UpdateModel(const GURL& url);
 
+  // On navigation away from NTP and Search pages, delete |ntp_web_contents_|.
+  void FlushNTP(const GURL& url);
+
   const bool is_search_enabled_;
 
   // Model object for UI that cares about search state.
-  scoped_ptr<SearchModel> model_;
+  SearchModel model_;
+
+  // Lazily created web contents for NTP.
+  scoped_ptr<content::WebContents> ntp_web_contents_;
 
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(SearchTabHelper);
 };
 
 }  // namespace search
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_SEARCH_SEARCH_TAB_HELPER_H_