Clean up NativeTheme (particularly CommonTheme).

ui/views/style/platform_style_mac.mm

 // 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/style/platform_style.h"
 
 #include "base/memory/ptr_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/paint_vector_icon.h"
@@ skipping 59 matching lines @@
   Button::ButtonState state = button.state();
   if (button.style() == Button::STYLE_BUTTON && button.is_default()) {
     // For convenience, we currently assume Mac wants the color corresponding to
     // the pressed state for default buttons.
     state = Button::STATE_PRESSED;
   }
   return color_by_state[state];
 }
 
 // static
 void PlatformStyle::ApplyLabelButtonTextStyle(

[Evan Stade, 2016/09/30 18:02:36]

this won't be necessary any more when harmony is default (there will be no
STYLE_BUTTON labelbuttons any more)

[tdanderson, 2016/09/30 21:00:56]

Is this something that will be obvious / you will remember when Harmony is
default, or should you add a TODO?

[Evan Stade, 2016/09/30 22:19:00]

should be obvious in the sense that it won't be called from anywhere any more. I
have a TODO in the relevant part of LabelButton.

     views::Label* label,
     ButtonColorByState* color_by_state) {
-  const ui::NativeTheme* theme = label->GetNativeTheme();
   ButtonColorByState& colors = *color_by_state;
-  colors[Button::STATE_PRESSED] =
-      theme->GetSystemColor(ui::NativeTheme::kColorId_ButtonHighlightColor);
+  colors[Button::STATE_PRESSED] = SK_ColorWHITE;
 }
 
 // static
 void PlatformStyle::OnTextfieldKeypressUnhandled() {
   NSBeep();
 }
 
 }  // namespace views