Added browser test for Captive Portal window ctor and dtor.

chrome/browser/chromeos/login/captive_portal_window_proxy.h

Index: chrome/browser/chromeos/login/captive_portal_window_proxy.h
diff --git a/chrome/browser/chromeos/login/captive_portal_window_proxy.h b/chrome/browser/chromeos/login/captive_portal_window_proxy.h
index 3ac5ae35be3c1eeff13ebee5202a0fcb1e077d59..1b49be355c4c2b01fe4cc40fb6371a7d8f4c1d20 100644
--- a/chrome/browser/chromeos/login/captive_portal_window_proxy.h
+++ b/chrome/browser/chromeos/login/captive_portal_window_proxy.h
@@ -63,6 +63,8 @@ class CaptivePortalWindowProxy : public views::WidgetObserver {
 
   // Overridden from views::WidgetObserver:
   virtual void OnWidgetClosing(views::Widget* widget) OVERRIDE;
+  virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE;
+  virtual void OnWidgetDestroyed(views::Widget* widget) OVERRIDE;
 
  private:
   friend class CaptivePortalWindowTest;
@@ -91,6 +93,10 @@ class CaptivePortalWindowProxy : public views::WidgetObserver {
   // Returns symbolic state name based on internal state.
   State GetState() const;
 
+  // When |widget| is not NULL and the same as |widget_| stops to observe
+  // notifications from |widget_| and resets it.
+  void DetachFromWidget(views::Widget* widget);
+
   // Not owned by this class.
   Delegate* delegate_;
   // Not owned by this class.