Fixed BubbleBorder sizing problems & added unit tests.

ui/views/bubble/tray_bubble_view.cc

Index: ui/views/bubble/tray_bubble_view.cc
diff --git a/ui/views/bubble/tray_bubble_view.cc b/ui/views/bubble/tray_bubble_view.cc
index 045a667b7c1fe21433b0963ae9c9a72196b822be..6091621620b1d595410b8be59d7f86effb690644 100644
--- a/ui/views/bubble/tray_bubble_view.cc
+++ b/ui/views/bubble/tray_bubble_view.cc
@@ -59,7 +59,6 @@ class MouseMoveDetectorHost : public MouseWatcherHost {
   virtual bool Contains(const gfx::Point& screen_point,
                         MouseEventType type) OVERRIDE;
  private:
-
   DISALLOW_COPY_AND_ASSIGN(MouseMoveDetectorHost);
 };
 
@@ -381,6 +380,7 @@ void TrayBubbleView::SetWidth(int width) {
 void TrayBubbleView::SetArrowPaintType(
     views::BubbleBorder::ArrowPaintType paint_type) {
   bubble_border_->set_paint_arrow(paint_type);
+  UpdateBubble();
 }
 
 gfx::Insets TrayBubbleView::GetBorderInsets() const {