Make html_contents_ in BallonViewImpl scoped_ptr.

chrome/browser/chromeos/notifications/balloon_view.h

Index: chrome/browser/chromeos/notifications/balloon_view.h
diff --git a/chrome/browser/chromeos/notifications/balloon_view.h b/chrome/browser/chromeos/notifications/balloon_view.h
index eb6840eb30241485e1f3e1aa925a0d8c1cc789d8..879f4f45605c68a4a311d2a3d146cf5c6d056a88 100644
--- a/chrome/browser/chromeos/notifications/balloon_view.h
+++ b/chrome/browser/chromeos/notifications/balloon_view.h
@@ -99,8 +99,8 @@ class BalloonViewImpl : public BalloonView,
   // Non-owned pointer to the balloon which owns this object.
   Balloon* balloon_;
 
-  // The renderer of the HTML contents. Pointer owned by the views hierarchy.
-  BalloonViewHost* html_contents_;
+  // The renderer of the HTML contents.
+  scoped_ptr<BalloonViewHost> html_contents_;
 
   // A widget for ControlView.
   scoped_ptr<views::Widget> control_view_host_;