Revert of X11: Use CopyFromParent colormap when possible

ui/base/x/x11_util_internal.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 UI_BASE_X_X11_UTIL_INTERNAL_H_
 #define UI_BASE_X_X11_UTIL_INTERNAL_H_
 
 // This file declares utility functions for X11 (Linux only).
 //
 // These functions require the inclusion of the Xlib headers. Since the Xlib
@@ skipping 83 matching lines @@
    private:
     Colormap colormap_;
   };
 
   XVisualManager();
 
   std::unordered_map<VisualID, std::unique_ptr<XVisualData>> visuals_;
 
   XDisplay* display_;
 
-  VisualID default_visual_id_;
-
-  // The system visual is usually the same as the default visual, but
-  // may not be in general.
   VisualID system_visual_id_;
   VisualID transparent_visual_id_;
 
   bool using_compositing_wm_;
   bool using_software_rendering_;
   bool have_gpu_argb_visual_;
 
   DISALLOW_COPY_AND_ASSIGN(XVisualManager);
 };
 #endif
 
 }  // namespace ui
 
 #endif  // UI_BASE_X_X11_UTIL_INTERNAL_H_