Change the account chooser on Win to look like in the mocks.

chrome/browser/ui/passwords/password_dialog_prompts.h

 // Copyright 2016 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.
 
 #ifndef CHROME_BROWSER_UI_PASSWORDS_PASSWORD_DIALOG_PROMPTS_H_
 #define CHROME_BROWSER_UI_PASSWORDS_PASSWORD_DIALOG_PROMPTS_H_
 
 #include "third_party/skia/include/core/SkColor.h"
 
 namespace content {
 class WebContents;
 }
 
 class PasswordDialogController;
 
 // Layout constants
 const int kDesiredWidth = 370;
 
 // The default inset from BubbleFrameView.
 const int kTitleTopInset = 12;
 
 // The color of the content in the autosign-in first run prompt.
 const SkColor kAutoSigninTextColor = SkColorSetRGB(0x64, 0x64, 0x64);
 
+// The hover color of the account chooser.
+const SkColor kButtonHoverColor = SkColorSetRGB(0xEA, 0xEA, 0xEA);
+
 // A platform-independent interface for the account chooser dialog.
 class AccountChooserPrompt {
  public:
   // Shows the account chooser dialog.
   virtual void ShowAccountChooser() = 0;
 
   // Notifies the UI element that it's controller is no longer managing the UI
   // element. The dialog should close.
   virtual void ControllerGone() = 0;
  protected:
@@ skipping 15 matching lines @@
 
 // Factory function for AccountChooserPrompt on desktop platforms.
 AccountChooserPrompt* CreateAccountChooserPromptView(
     PasswordDialogController* controller, content::WebContents* web_contents);
 
 // Factory function for AutoSigninFirstRunPrompt on desktop platforms.
 AutoSigninFirstRunPrompt* CreateAutoSigninPromptView(
     PasswordDialogController* controller, content::WebContents* web_contents);
 
 #endif  // CHROME_BROWSER_UI_PASSWORDS_PASSWORD_DIALOG_PROMPTS_H_