Remove hover highlight on Harmony checkboxes.

ui/views/controls/button/checkbox.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 UI_VIEWS_CONTROLS_BUTTON_CHECKBOX_H_
 #define UI_VIEWS_CONTROLS_BUTTON_CHECKBOX_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 22 matching lines @@
   void set_listener(ButtonListener* listener) { listener_ = listener; }
 
   // Sets/Gets whether or not the checkbox is checked.
   virtual void SetChecked(bool checked);
   bool checked() const { return checked_; }
 
  protected:
   // Returns whether MD is enabled; exists for the sake of brevity.
   static bool UseMd();
 
-  // Overridden from LabelButton:
+  // LabelButton:
   const char* GetClassName() const override;
   void GetAccessibleNodeData(ui::AXNodeData* node_data) override;
   void OnPaint(gfx::Canvas* canvas) override;
   void OnFocus() override;
   void OnBlur() override;
   void OnNativeThemeChanged(const ui::NativeTheme* theme) override;
   std::unique_ptr<InkDropRipple> CreateInkDropRipple() const override;
+  std::unique_ptr<InkDropHighlight> CreateInkDropHighlight() const override;
   SkColor GetInkDropBaseColor() const override;
   gfx::ImageSkia GetImage(ButtonState for_state) const override;
 
   // Set the image shown for each button state depending on whether it is
   // [checked] or [focused].
   void SetCustomImage(bool checked,
                       bool focused,
                       ButtonState for_state,
                       const gfx::ImageSkia& image);
 
   // Paints a focus indicator for the view.
   virtual void PaintFocusRing(gfx::Canvas* canvas, const cc::PaintFlags& flags);
 
   // Gets the vector icon to use based on the current state of |checked_|.
   virtual const gfx::VectorIcon& GetVectorIcon() const;
 
  private:
-  // Overridden from Button:
+  // Button:
   void NotifyClick(const ui::Event& event) override;
 
   ui::NativeTheme::Part GetThemePart() const override;
   void GetExtraParams(ui::NativeTheme::ExtraParams* params) const override;
 
   // True if the checkbox is checked.
   bool checked_;
 
   // The images for each button node_data.
   gfx::ImageSkia images_[2][2][STATE_COUNT];
 
   DISALLOW_COPY_AND_ASSIGN(Checkbox);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_BUTTON_CHECKBOX_H_