Test aria-pressed=mixed on windows

ui/views/controls/button/custom_button.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/button/custom_button.h"
 
 #include "ui/accessibility/ax_node_data.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
 #include "ui/events/keycodes/keyboard_codes.h"
@@ skipping 341 matching lines @@
   AnimateInkDrop(InkDropState::HIDDEN, nullptr /* event */);
 }
 
 void CustomButton::GetAccessibleNodeData(ui::AXNodeData* node_data) {
   Button::GetAccessibleNodeData(node_data);
   switch (state_) {
     case STATE_HOVERED:
       node_data->AddState(ui::AX_STATE_HOVERED);
       break;
     case STATE_PRESSED:
-      node_data->AddState(ui::AX_STATE_PRESSED);
+      node_data->AddIntAttribute(ui::AX_ATTR_PRESSED_STATE,
+                                 ui::AX_BUTTON_STATE_TRUE);
       break;
     case STATE_DISABLED:
       node_data->AddState(ui::AX_STATE_DISABLED);
       break;
     case STATE_NORMAL:
     case STATE_COUNT:
       // No additional accessibility node_data set for this button node_data.
       break;
   }
   if (enabled()) {
@@ skipping 124 matching lines @@
         GetInkDrop()->GetTargetInkDropState() ==
             views::InkDropState::ALTERNATE_ACTION_PENDING) {
       AnimateInkDrop(views::InkDropState::HIDDEN,
                      ui::LocatedEvent::FromIfValid(&event));
     }
   }
   Button::OnClickCanceled(event);
 }
 
 }  // namespace views