Separate the logic of popup alignment and workarea handling as delegate.

ui/message_center/views/message_popup_collection.h

Index: ui/message_center/views/message_popup_collection.h
diff --git a/ui/message_center/views/message_popup_collection.h b/ui/message_center/views/message_popup_collection.h
index 955af32ddb5e2a25363f4de44b3829b2d7ce7592..8d6d644c68a262a800e538ba96a514024d044f79 100644
--- a/ui/message_center/views/message_popup_collection.h
+++ b/ui/message_center/views/message_popup_collection.h
@@ -12,8 +12,6 @@
 #include "base/gtest_prod_util.h"
 #include "base/memory/weak_ptr.h"
 #include "base/timer/timer.h"
-#include "ui/gfx/display.h"
-#include "ui/gfx/display_observer.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
 #include "ui/message_center/message_center_export.h"
@@ -30,12 +28,8 @@ namespace views {
 class Widget;
 }
 
-namespace ash {
-class WebNotificationTrayTest;
-FORWARD_DECLARE_TEST(WebNotificationTrayTest, ManyPopupNotifications);
-}
-
 namespace gfx {
+class Display;
 class Screen;
 }
 
@@ -47,13 +41,7 @@ class MessagePopupCollectionTest;
 class MessageCenter;
 class MessageCenterTray;
 class MessageViewContextMenuController;
-
-enum PopupAlignment {
-  POPUP_ALIGNMENT_TOP = 1 << 0,
-  POPUP_ALIGNMENT_LEFT = 1 << 1,
-  POPUP_ALIGNMENT_BOTTOM = 1 << 2,
-  POPUP_ALIGNMENT_RIGHT = 1 << 3,
-};
+class PopupAlignmentDelegate;
 
 // Container for popup toasts. Because each toast is a frameless window rather
 // than a view in a bubble, now the container just manages all of those toasts.
@@ -62,17 +50,15 @@ enum PopupAlignment {
 // be slightly different.
 class MESSAGE_CENTER_EXPORT MessagePopupCollection
     : public MessageCenterController,
-      public MessageCenterObserver,
-      public gfx::DisplayObserver {
+      public MessageCenterObserver {
  public:
   // |parent| specifies the parent widget of the toast windows. The default
   // parent will be used for NULL. Usually each icon is spacing against its
-  // predecessor. If |first_item_has_no_margin| is set however the first item
-  // does not space against the tray.
+  // predecessor.
   MessagePopupCollection(gfx::NativeView parent,
                          MessageCenter* message_center,
                          MessageCenterTray* tray,
-                         bool first_item_has_no_margin);
+                         PopupAlignmentDelegate* alignment_delegate);
   virtual ~MessagePopupCollection();
 
   // Overridden from MessageCenterController:
@@ -109,30 +95,14 @@ class MESSAGE_CENTER_EXPORT MessagePopupCollection
   // toast is irrevocably closed (such as within RemoveToast).
   void ForgetToast(ToastContentsView* toast);
 
-  // Updates |work_area_| and re-calculates the alignment of notification toasts
-  // rearranging them if necessary.
-  // This is separated from methods from OnDisplayMetricsChanged(), since
-  // sometimes the display info has to be specified directly. One example is
-  // shelf's auto-hide change. When the shelf in ChromeOS is temporarily shown
-  // from auto hide status, it doesn't change the display's work area but the
-  // actual work area for toasts should be resized.
-  void SetDisplayInfo(const gfx::Rect& work_area,
-                      const gfx::Rect& screen_bounds);
-
-  // Overridden from gfx::DislayObserver:
-  virtual void OnDisplayAdded(const gfx::Display& new_display) OVERRIDE;
-  virtual void OnDisplayRemoved(const gfx::Display& old_display) OVERRIDE;
-  virtual void OnDisplayMetricsChanged(const gfx::Display& display,
-                                       uint32_t metrics) OVERRIDE;
+  // Called when the display bounds has been changed. Used in Windows only.
+  void OnDisplayMetricsChanged(const gfx::Display& display);
 
   // Used by ToastContentsView to locate itself.
   gfx::NativeView parent() const { return parent_; }
 
  private:
-  FRIEND_TEST_ALL_PREFIXES(ash::WebNotificationTrayTest,
-                           ManyPopupNotifications);
   friend class test::MessagePopupCollectionTest;
-  friend class ash::WebNotificationTrayTest;
   typedef std::list<ToastContentsView*> Toasts;
 
   // Iterates toasts and starts closing them.
@@ -141,9 +111,6 @@ class MESSAGE_CENTER_EXPORT MessagePopupCollection
   // Called by ToastContentsView when its window is closed.
   void RemoveToast(ToastContentsView* toast, bool mark_as_shown);
 
-  // Returns the x-origin for the given toast bounds in the current work area.
-  int GetToastOriginX(const gfx::Rect& toast_bounds) const;
-
   // Creates new widgets for new toast notifications, and updates |toasts_| and
   // |widgets_| correctly.
   void UpdateWidgets();
@@ -156,8 +123,6 @@ class MESSAGE_CENTER_EXPORT MessagePopupCollection
   // See crbug.com/224089
   void RepositionWidgetsWithTarget();
 
-  void ComputePopupAlignment(gfx::Rect work_area, gfx::Rect screen_bounds);
-
   // The base line is an (imaginary) line that would touch the bottom of the
   // next created notification if bottom-aligned or its top if top-aligned.
   int GetBaseLine(ToastContentsView* last_toast) const;
@@ -187,13 +152,8 @@ class MESSAGE_CENTER_EXPORT MessagePopupCollection
   MessageCenter* message_center_;
   MessageCenterTray* tray_;
   Toasts toasts_;
-  gfx::Rect work_area_;
-  int64 display_id_;
-  gfx::Screen* screen_;
 
-  // Specifies which corner of the screen popups should show up. This should
-  // ideally be the same corner the notification area (systray) is at.
-  PopupAlignment alignment_;
+  PopupAlignmentDelegate* alignment_delegate_;
 
   int defer_counter_;
 
@@ -215,9 +175,6 @@ class MESSAGE_CENTER_EXPORT MessagePopupCollection
   // Weak, only exists temporarily in tests.
   scoped_ptr<base::RunLoop> run_loop_for_test_;
 
-  // True if the first item should not have spacing against the tray.
-  bool first_item_has_no_margin_;
-
   scoped_ptr<MessageViewContextMenuController> context_menu_controller_;
 
   // Gives out weak pointers to toast contents views which have an unrelated