Allow dialogs to use a custom View as their title.

ui/views/bubble/bubble_dialog_delegate.h

Index: ui/views/bubble/bubble_dialog_delegate.h
diff --git a/ui/views/bubble/bubble_dialog_delegate.h b/ui/views/bubble/bubble_dialog_delegate.h
index e027988df18d514041e98681d6e540a69cbdd964..67cce63b5cbca6498692bdb1bed40aaa7f45bc13 100644
--- a/ui/views/bubble/bubble_dialog_delegate.h
+++ b/ui/views/bubble/bubble_dialog_delegate.h
@@ -57,6 +57,9 @@ class VIEWS_EXPORT BubbleDialogDelegateView : public DialogDelegateView,
   void OnWidgetBoundsChanged(Widget* widget,
                              const gfx::Rect& new_bounds) override;
 
+  // View:
+  void AddedToWidget() override;

[sky, 2017/06/09 23:49:16]

Move up to WidgetDelegateView section above.

[Bret, 2017/06/15 22:20:34]

Done.

+
   bool close_on_deactivate() const { return close_on_deactivate_; }
   void set_close_on_deactivate(bool close) { close_on_deactivate_ = close; }
 
@@ -123,6 +126,9 @@ class VIEWS_EXPORT BubbleDialogDelegateView : public DialogDelegateView,
   // bounds change as a result of the widget's bounds changing.
   void OnAnchorBoundsChanged();
 
+  // Called when the title of the dialog needs to be updated.
+  void PropagateUpdateTitleView(View* title_view);
+
  protected:
   BubbleDialogDelegateView();
   BubbleDialogDelegateView(View* anchor_view, BubbleBorder::Arrow arrow);
@@ -134,6 +140,15 @@ class VIEWS_EXPORT BubbleDialogDelegateView : public DialogDelegateView,
   // (The default is MediumFont).
   virtual const gfx::FontList& GetTitleFontList() const;
 
+  // Returns a custom view to use as the title of the dialog.
+  virtual View* CreateTitleView();
+
+  // Called when the title of the dialog needs to be updated and a custom title
+  // view is being used.
+  virtual void UpdateTitleView(View* view,
+                               base::string16 title_text,
+                               bool visible) {}
+
   // View overrides:
   void OnNativeThemeChanged(const ui::NativeTheme* theme) override;