Switch tab.cc to use an empty border for the contents.

chrome/browser/ui/views/tabs/tab.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_TAB_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_TAB_H_
 
 #include <list>
 #include <string>
 
@@ skipping 270 matching lines @@
   }
 
   // Recalculates the correct |button_color_| and resets the title, media
   // indicator, and close button colors if necessary.  This should be called any
   // time the theme or active state may have changed.
   void OnButtonColorMaybeChanged();
 
   // Schedules repaint task for icon.
   void ScheduleIconPaint();
 
-  // Returns the rect that can be used for content inside the tab borders.
-  gfx::Rect GetInteriorBounds() const;
-
   // Returns the rectangle for the light bar in immersive mode.
   gfx::Rect GetImmersiveBarRect() const;
 
   // Gets the tab id and frame id.
   void GetTabIdAndFrameId(views::Widget* widget,
                           int* tab_id,
                           int* frame_id) const;
 
   // Performs a one-time initialization of static resources such as tab images.
   static void InitTabResources();
@@ skipping 95 matching lines @@
   SkColor button_color_;
 
   // As the majority of the tabs are inactive, and painting tabs is slowish,
   // we cache a handful of the inactive tab backgrounds here.
   static ImageCache* image_cache_;
 
   DISALLOW_COPY_AND_ASSIGN(Tab);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_TAB_H_