Use standard icon/title in global error bubble

ui/views/widget/widget_delegate.h

 // 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.
 
 #ifndef UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_
 #define UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 61 matching lines @@
 
   // Returns the title to be read with screen readers.
   virtual base::string16 GetAccessibleWindowTitle() const;
 
   // Returns the text to be displayed in the window title.
   virtual base::string16 GetWindowTitle() const;
 
   // Returns true if the window should show a title in the title bar.
   virtual bool ShouldShowWindowTitle() const;
 
+  // Returns the icon to be displayed in the window title.
+  virtual gfx::ImageSkia GetWindowTitleIcon();

[msw, 2015/02/18 18:48:15]

Use GetWindowIcon and ShouldShowWindowIcon below instead.

[xiaoling, 2015/02/18 19:03:02]

Can I? Excellent if I can. What's the purpose of the WindowIcon? Will I break
something if I overload the meaning of that icon?

[msw, 2015/02/18 19:14:44]

You should definitely use those. They're already used for popup windows in
Chrome, perhaps app windows and more. Regardless, they're currently unused by
the BubbleDelegate[View] subclasses, and using them for this purpose (nearly
identical to the other window icons) is entirely reasonable.

+
+  // Returns true if the window should show an icon in the title bar.
+  virtual bool ShouldShowWindowTitleIcon() const;
+
   // Returns true if the window should show a close button in the title bar.
   virtual bool ShouldShowCloseButton() const;
 
   // Returns true if the window should handle standard system commands, such as
   // close, minimize, maximize.
   virtual bool ShouldHandleSystemCommands() const;
 
   // Returns the app icon for the window. On Windows, this is the ICON_BIG used
   // in Alt-Tab list and Win7's taskbar.
   virtual gfx::ImageSkia GetWindowAppIcon();
@@ skipping 122 matching lines @@
   // View:
   const char* GetClassName() const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WidgetDelegateView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_