First stab at touch optimized omnibox auto-complete per sgabriel's mocks.

chrome/browser/ui/views/autocomplete/autocomplete_popup_contents_view.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_VIEWS_AUTOCOMPLETE_AUTOCOMPLETE_POPUP_CONTENTS_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_AUTOCOMPLETE_AUTOCOMPLETE_POPUP_CONTENTS_VIEW_H_
 #pragma once
 
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/autocomplete/autocomplete.h"
@@ skipping 14 matching lines @@
 namespace views {
 class BubbleBorder;
 }
 
 // A view representing the contents of the autocomplete popup.
 class AutocompletePopupContentsView : public views::View,
                                       public AutocompleteResultViewModel,
                                       public AutocompletePopupView,
                                       public ui::AnimationDelegate {
  public:
+  // Creates the appropriate type of omnibox dropdown for the
+  // current environment, e.g. desktop vs. touch optimized layout.
+  static AutocompletePopupContentsView* CreateForEnvironment(
+      const gfx::Font& font,
+      OmniboxView* omnibox_view,
+      AutocompleteEditModel* edit_model,
+      views::View* location_bar);
+
   AutocompletePopupContentsView(const gfx::Font& font,

[Peter Kasting, 2012/05/07 21:03:12]

Nit: This can become protected.

[Jói, 2012/05/10 18:33:07]

Done.

                                 OmniboxView* omnibox_view,
                                 AutocompleteEditModel* edit_model,
                                 views::View* location_bar);
   virtual ~AutocompletePopupContentsView();
 
+  // Call immediately after construction.

[Peter Kasting, 2012/05/07 21:03:12]

Nit: This can become private.

[Jói, 2012/05/10 18:33:07]

Done.

+  void Init();
+
   // Returns the bounds the popup should be shown at. This is the display bounds
   // and includes offsets for the dropshadow which this view's border renders.
   gfx::Rect GetPopupBounds() const;
 
   virtual void LayoutChildren();
 
   // Overridden from AutocompletePopupView:
   virtual bool IsOpen() const OVERRIDE;
   virtual void InvalidateLine(size_t line) OVERRIDE;
   virtual void UpdatePopupAppearance() OVERRIDE;
@@ skipping 108 matching lines @@
   // The popup sizes vertically using an animation when the popup is getting
   // shorter (not larger, that makes it look "slow").
   ui::SlideAnimation size_animation_;
   gfx::Rect start_bounds_;
   gfx::Rect target_bounds_;
 
   DISALLOW_COPY_AND_ASSIGN(AutocompletePopupContentsView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_AUTOCOMPLETE_AUTOCOMPLETE_POPUP_CONTENTS_VIEW_H_