Introduce BubbleDialogDelegateView, which extends DialogDelegateView

ui/views/window/dialog_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_WINDOW_DIALOG_DELEGATE_H_
 #define UI_VIEWS_WINDOW_DIALOG_DELEGATE_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/strings/string16.h"
@@ skipping 38 matching lines @@
   // Override this function to display an extra view adjacent to the buttons.
   // Overrides may construct the view; this will only be called once per dialog.
   virtual View* CreateExtraView();
 
   // Override this function to adjust the padding between the extra view and
   // the confirm/cancel buttons. Note that if there are no buttons, this will
   // not be used.
   // If a custom padding should be used, returns true and populates |padding|.
   virtual bool GetExtraViewPadding(int* padding);
 
-  // Override this function to display an extra view in the titlebar.
-  // Overrides may construct the view; this will only be called once per dialog.
-  // Note: this only works for new style dialogs.
-  virtual View* CreateTitlebarExtraView();

[Evan Stade, 2016/02/23 19:02:36]

this wasn't being used anywhere

-
   // Override this function to display a footnote view below the buttons.
   // Overrides may construct the view; this will only be called once per dialog.
   virtual View* CreateFootnoteView();
 
   // For Dialog boxes, if there is a "Cancel" button or no dialog button at all,
   // this is called when the user presses the "Cancel" button or the Esc key.
   // It can also be called on a close action if |Close| has not been
   // overridden. This function should return true if the window can be closed
   // after it returns, or false if it must remain open.
   virtual bool Cancel();
@@ skipping 70 matching lines @@
   void ViewHierarchyChanged(
       const ViewHierarchyChangedDetails& details) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DialogDelegateView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WINDOW_DIALOG_DELEGATE_H_