Makes the touch tabstrip scroll so that tabs opened in the background

chrome/browser/ui/views/tabs/touch_tab_strip_layout.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_TABS_TOUCH_TAB_STRIP_LAYOUT_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_TOUCH_TAB_STRIP_LAYOUT_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "ui/gfx/size.h"
@@ skipping 78 matching lines @@
  private:
   friend class TouchTabStripLayoutTest;
 
   // Sets the x-coordinate normal tabs start at, width mini-tab count and
   // active index at once.
   void Reset(int x, int width, int mini_tab_count, int active_index);
 
   // Resets to an ideal layout state.
   void ResetToIdealState();
 
+  // Makes |index| visible. This is used when a new tab is added that isn't
+  // active.
+  void MakeVisible(int index);
+
   // Returns the x-coordinate for the active tab constrained by the current tab
   // counts.
   int ConstrainActiveX(int x) const;
 
   // Reset the bounds of the active tab (based on ConstrainActiveX()) and resets
   // the bounds of the remaining tabs by way of LayoutUsingCurrent*.
   void SetActiveBoundsAndLayoutFromActiveTab();
 
   // Sets the bounds of the tabs after |index| relative to the position of the
   // tab at |index|. Each tab is placed |tab_offset()| pixels after the previous
@@ skipping 39 matching lines @@
   // against the right side.
   int GetMaxXCompressed(int index) const;
 
   // Returns the min x-coordinate for the tab at |index|. This is relative
   // to the |active_index()| and is only useful when the active tab is pushed
   // against the left side.
   int GetMinXCompressed(int index) const;
 
   // Width needed to display |count| tabs.
   int width_for_count(int count) const {
-    return count == 0 ? 0 :
-        (count * size_.width()) + (std::max(count - 1, 0) * padding_);
+    return (count * size_.width()) + (std::max(count - 1, 0) * padding_);
   }
 
   // Padding needed for |count| stacked tabs.
   int stacked_padding_for_count(int count) const {
     return std::min(count, max_stacked_count_) * stacked_padding_;
   }
 
   // Max stacked padding.
   int max_stacked_width() const {
     return stacked_padding_ * max_stacked_count_;
@@ skipping 40 matching lines @@
   // Number of mini-tabs.
   int mini_tab_count_;
 
   // Index of the active tab.
   int active_index_;
 
   DISALLOW_COPY_AND_ASSIGN(TouchTabStripLayout);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_TOUCH_TAB_STRIP_LAYOUT_H_