Remove --background-color-instead-of-checkerboard flag.

cc/base/switches.cc

 // 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.
 
 #include "cc/base/switches.h"
 
 #include "base/command_line.h"
 
 namespace cc {
 namespace switches {
 
-// On platforms where checkerboards are used, prefer background colors instead
-// of checkerboards.
-const char kBackgroundColorInsteadOfCheckerboard[] =
-    "background-color-instead-of-checkerboard";
-
 // Disables LCD text.
 const char kDisableLCDText[] = "disable-lcd-text";
 
 const char kDisableThreadedAnimation[] = "disable-threaded-animation";
 
 // Disables layer-edge anti-aliasing in the compositor.
 const char kDisableCompositedAntialiasing[] =
     "disable-composited-antialiasing";
 
 // Paint content on the main thread instead of the compositor thread.
@@ skipping 170 matching lines @@
   if (command_line.HasSwitch(switches::kDisableMapImage))
     return false;
   else if (command_line.HasSwitch(switches::kEnableMapImage))
     return true;
 
   return false;
 }
 
 }  // namespace switches
 }  // namespace cc