Do not activate system tray bubble by default

ash/common/system/date/date_view.h

Index: ash/common/system/date/date_view.h
diff --git a/ash/common/system/date/date_view.h b/ash/common/system/date/date_view.h
index 97a96b2dd273234748cb464447c43ad13675dfb5..87513bb8bfd6e2f14f6b08da15d26e1dd69d34c0 100644
--- a/ash/common/system/date/date_view.h
+++ b/ash/common/system/date/date_view.h
@@ -39,7 +39,7 @@ class ASH_EXPORT BaseDateTimeView : public ActionableView {
   void GetAccessibleState(ui::AXViewState* state) override;
 
  protected:
-  BaseDateTimeView();
+  explicit BaseDateTimeView(SystemTrayItem* owner);
 
   // Updates labels to display the current time.
   virtual void UpdateTextInternal(const base::Time& now);
@@ -64,7 +64,7 @@ class ASH_EXPORT BaseDateTimeView : public ActionableView {
 // Popup view used to display the date and day of week.
 class ASH_EXPORT DateView : public BaseDateTimeView {
  public:
-  DateView();
+  explicit DateView(SystemTrayItem* owner);
   ~DateView() override;
 
   // Sets the action the view should take. An actionable date view gives visual