Fix appearance of disabled VectorIconButtons.

ui/views/controls/button/vector_icon_button.cc

 // Copyright 2015 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 "ui/views/controls/button/vector_icon_button.h"
 
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/gfx/color_palette.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/paint_vector_icon.h"
@@ skipping 28 matching lines @@
 void VectorIconButton::SetIcon(gfx::VectorIconId id) {
   id_ = id;
 
   if (!border()) {
     SetBorder(views::Border::CreateEmptyBorder(
         kButtonExtraTouchSize, kButtonExtraTouchSize, kButtonExtraTouchSize,
         kButtonExtraTouchSize));
   }
 }
 
-void VectorIconButton::OnEnabledChanged() {
-  OnThemeChanged();
-}
-
 void VectorIconButton::OnThemeChanged() {
   SkColor icon_color =
       color_utils::DeriveDefaultIconColor(delegate_->GetVectorIconBaseColor());
   gfx::ImageSkia image = gfx::CreateVectorIcon(id_, icon_color);
   SetImage(views::CustomButton::STATE_NORMAL, &image);
   image = gfx::CreateVectorIcon(id_, SkColorSetA(icon_color, 0xff / 2));
   SetImage(views::CustomButton::STATE_DISABLED, &image);
   set_ink_drop_base_color(icon_color);
 }
 
 void VectorIconButton::OnNativeThemeChanged(const ui::NativeTheme* theme) {
   OnThemeChanged();
 }
 
 }  // namespace views