combobox: don't animate state changes in TransparentButton

ui/views/controls/combobox/combobox.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 "ui/views/controls/combobox/combobox.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 98 matching lines @@
 
   bounds.ClampToCenteredSize(arrow_size);
   return bounds;
 }
 
 // The transparent button which holds a button state but is not rendered.
 class TransparentButton : public CustomButton {
  public:
   TransparentButton(ButtonListener* listener)
       : CustomButton(listener) {
     SetAnimationDuration(LabelButton::kHoverAnimationDurationMs);

[Evan Stade, 2016/09/09 18:37:13]

why is this here?

[Elly Fong-Jones, 2016/09/12 11:46:40]

Your guess is as good as mine. It was added in the implementation of "action
style" comboboxes in https://codereview.chromium.org/59383003 and it seems like
this specific line was copied verbatim from LabelButton's constructor. I would
rather like to remove this entire class.

[Evan Stade, 2016/09/12 14:51:17]

It seems the line you're adding defeats the purpose of SetAnimationDuration. I
think you're breaking PaintButtons below (only used for action style comboboxes,
but one of those still exists for now). You should probably either set the
animation duration or set animate false depending on the style of combobox.

     SetFocusBehavior(FocusBehavior::NEVER);
     set_notify_action(PlatformStyle::kMenuNotifyActivationAction);
+    set_animate_on_state_change(false);
 
     if (UseMd()) {
       SetInkDropMode(PlatformStyle::kUseRipples ? InkDropMode::ON
                                                 : InkDropMode::OFF);
       set_has_ink_drop_action_on_click(true);
     }
   }
   ~TransparentButton() override {}
 
   bool OnMousePressed(const ui::MouseEvent& mouse_event) override {
@@ skipping 857 matching lines @@
 }
 
 int Combobox::GetArrowContainerWidth() const {
   int padding = style_ == STYLE_NORMAL
                     ? PlatformStyle::kComboboxNormalArrowPadding * 2
                     : kActionLeftPadding + kActionRightPadding;
   return ArrowSize().width() + padding;
 }
 
 }  // namespace views