[Views] Add a capability to the bubble delegate to be able to show the title in BaseFont.

ui/views/bubble/bubble_delegate.cc

Index: ui/views/bubble/bubble_delegate.cc
diff --git a/ui/views/bubble/bubble_delegate.cc b/ui/views/bubble/bubble_delegate.cc
index 0b890eca5d0ff4ef21d8eaf1cc65f5d3a8076ced..747d26b75795fbb96e94285d149693a2cdb2004c 100644
--- a/ui/views/bubble/bubble_delegate.cc
+++ b/ui/views/bubble/bubble_delegate.cc
@@ -5,6 +5,7 @@
 #include "ui/views/bubble/bubble_delegate.h"
 
 #include "ui/accessibility/ax_view_state.h"
+#include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/rect.h"
 #include "ui/native_theme/native_theme.h"
@@ -131,6 +132,7 @@ View* BubbleDelegateView::GetContentsView() {
 NonClientFrameView* BubbleDelegateView::CreateNonClientFrameView(
     Widget* widget) {
   BubbleFrameView* frame = new BubbleFrameView(margins());
+  frame->SetTitleFontList(GetTitleFontList());
   BubbleBorder::Arrow adjusted_arrow = arrow();
   if (base::i18n::IsRTL())
     adjusted_arrow = BubbleBorder::horizontal_mirror(adjusted_arrow);
@@ -177,6 +179,11 @@ void BubbleDelegateView::OnWidgetBoundsChanged(Widget* widget,
     SizeToContents();
 }
 
+const gfx::FontList& BubbleDelegateView::GetTitleFontList() const {
+  ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
+  return rb.GetFontList(ui::ResourceBundle::MediumFont);
+}
+
 View* BubbleDelegateView::GetAnchorView() const {
   return ViewStorage::GetInstance()->RetrieveView(anchor_view_storage_id_);
 }