Refactor ChooserDialogView to use borders instead of content margins.

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 176 matching lines @@
 DialogDelegate* DialogDelegate::AsDialogDelegate() {
   return this;
 }
 
 ClientView* DialogDelegate::CreateClientView(Widget* widget) {
   return new DialogClientView(widget, GetContentsView());
 }
 
 NonClientFrameView* DialogDelegate::CreateNonClientFrameView(Widget* widget) {
   if (ShouldUseCustomFrame())
-    return CreateDialogFrameView(widget, gfx::Insets());
+    return CreateDialogFrameView(widget);
   return WidgetDelegate::CreateNonClientFrameView(widget);
 }
 
 // static
-NonClientFrameView* DialogDelegate::CreateDialogFrameView(
-    Widget* widget,
-    const gfx::Insets& content_margins) {
+NonClientFrameView* DialogDelegate::CreateDialogFrameView(Widget* widget) {
   BubbleFrameView* frame = new BubbleFrameView(
       LayoutProvider::Get()->GetInsetsMetric(INSETS_DIALOG_TITLE),
-      content_margins);
+      gfx::Insets());
   const BubbleBorder::Shadow kShadow = BubbleBorder::SMALL_SHADOW;
   std::unique_ptr<BubbleBorder> border(
       new BubbleBorder(BubbleBorder::FLOAT, kShadow, gfx::kPlaceholderColor));
   border->set_use_theme_background_color(true);
   frame->SetBubbleBorder(std::move(border));
   DialogDelegate* delegate = widget->widget_delegate()->AsDialogDelegate();
   if (delegate)
     frame->SetFootnoteView(delegate->CreateFootnoteView());
   return frame;
 }
@@ skipping 46 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