Adds ability to render omnibox as a view above the page.

chrome/browser/ui/views/frame/contents_container.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_VIEWS_FRAME_CONTENTS_CONTAINER_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_CONTENTS_CONTAINER_H_
 #pragma once
 
 #include "ui/views/view.h"
 
 namespace content {
 class WebContents;
 }
 
 // ContentsContainer is responsible for managing the WebContents views.
 // ContentsContainer has up to two children: one for the currently active
 // WebContents and one for instant's WebContents.
 class ContentsContainer : public views::View {
  public:
   // Internal class name
   static const char kViewClassName[];
 
   explicit ContentsContainer(views::View* active);
   virtual ~ContentsContainer();
 
+  // View positioned above the contents. The returned view is owned by this.
+  // The header is sized to the preferred height of its single child (width
+  // fills the available width). If the child is not visible the header is
+  // sized to an empty rect.
+  views::View* header();
+
   // Makes the preview view the active view and nulls out the old active view.
   // It's assumed the caller will delete or remove the old active view
   // separately.
   void MakePreviewContentsActiveContents();
 
   // Sets the preview view. This does not delete the old.
   void SetPreview(views::View* preview,
                   content::WebContents* preview_web_contents);
 
   content::WebContents* preview_web_contents() const {
     return preview_web_contents_;
   }
 
   // Sets the active top margin.
   void SetActiveTopMargin(int margin);
 
   // Returns the bounds of the preview. If the preview isn't active this
   // retuns the bounds the preview would be shown at.
   gfx::Rect GetPreviewBounds();
 
   // View overrides:
   virtual void Layout() OVERRIDE;
   virtual std::string GetClassName() const OVERRIDE;
 
  private:
+  class HeaderView;
+
+  HeaderView* header_;
   views::View* active_;
   views::View* preview_;
   content::WebContents* preview_web_contents_;
 
   // The margin between the top and the active view. This is used to make the
   // preview overlap the bookmark bar on the new tab page.
   int active_top_margin_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentsContainer);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_FRAME_CONTENTS_CONTAINER_H_