Ensure default dialog button focus remains after a dialog update.

chrome/browser/ui/views/extensions/extension_install_dialog_view.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 "chrome/browser/ui/views/extensions/extension_install_dialog_view.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <string>
 #include <utility>
@@ skipping 63 matching lines @@
 constexpr int kPermissionsLeftColumnWidth = 250;
 
 // Width of the left column of the dialog when the extension requests no
 // permissions.
 constexpr int kNoPermissionsLeftColumnWidth = 200;
 
 // Width of the left column for external install prompts. The text is long in
 // this case, so make it wider than normal.
 constexpr int kExternalInstallLeftColumnWidth = 350;
 
+// Time delay before the install button is enabled after initial display.
+int g_install_delay_in_ms = 500;
+
 // Get the appropriate indentation for an item if its parent is using bullet
 // points. If the parent is using bullets for its items, then a padding of one
 // unit will make the child item (which has no bullet) look like a sibling of
 // its parent. Therefore increase the indentation by one more unit to show that
 // it is in fact a child item (with no missing bullet) and not a sibling.
 int GetLeftPaddingForBulletedItems(bool parent_bulleted) {
   return ChromeLayoutProvider::Get()->GetDistanceMetric(
              views::DISTANCE_RELATED_CONTROL_HORIZONTAL) *
          (parent_bulleted ? 2 : 1);
 }
 
-// Time delay before the install button is enabled after initial display.
-int g_install_delay_in_ms = 500;
-
 void AddResourceIcon(const gfx::ImageSkia* skia_image, void* data) {
   views::View* parent = static_cast<views::View*>(data);
   views::ImageView* image_view = new views::ImageView();
   image_view->SetImage(*skia_image);
   parent->AddChildView(image_view);
 }
 
 // Creates a string for displaying |message| to the user. If it has to look
 // like a entry in a bullet point list, one is added.
 base::string16 PrepareForDisplay(const base::string16& message,
@@ skipping 682 matching lines @@
   gfx::ImageSkia icon = gfx::CreateVectorIcon(
       expanded ? kCaretUpIcon : kCaretDownIcon, gfx::kChromeIconGrey);
   arrow_toggle_->SetImage(views::Button::STATE_NORMAL, &icon);
 }
 
 // static
 ExtensionInstallPrompt::ShowDialogCallback
 ExtensionInstallPrompt::GetViewsShowDialogCallback() {
   return base::Bind(&ShowExtensionInstallDialogImpl);
 }