views: don't snap dialogs with no buttons

ui/views/window/dialog_delegate.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/window/dialog_delegate.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 115 matching lines @@
   button->SetEnabled(IsDialogButtonEnabled(type));
   bool is_default = type == GetDefaultDialogButton();
   if (!PlatformStyle::kDialogDefaultButtonCanBeCancel &&
       type == ui::DIALOG_BUTTON_CANCEL) {
     is_default = false;
   }
   button->SetIsDefault(is_default);
 }
 
 bool DialogDelegate::ShouldSnapFrameWidth() const {
-  return true;
+  return GetDialogButtons() != ui::DIALOG_BUTTON_NONE;

[sky, 2017/05/12 17:28:07]

Would a better fix be to have BubbleDialogDelegateView override and return
false?

 }
 
 int DialogDelegate::GetDialogButtons() const {
   return ui::DIALOG_BUTTON_OK | ui::DIALOG_BUTTON_CANCEL;
 }
 
 int DialogDelegate::GetDefaultDialogButton() const {
   if (GetDialogButtons() & ui::DIALOG_BUTTON_OK)
     return ui::DIALOG_BUTTON_OK;
   if (GetDialogButtons() & ui::DIALOG_BUTTON_CANCEL)
@@ skipping 121 matching lines @@
   node_data->role = ui::AX_ROLE_DIALOG;
 }
 
 void DialogDelegateView::ViewHierarchyChanged(
     const ViewHierarchyChangedDetails& details) {
   if (details.is_add && details.child == this && GetWidget())
     NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, true);
 }
 
 }  // namespace views