Change infobar creation to use a public static Create() method on the infobar delegate classes.

chrome/browser/api/infobars/confirm_infobar_delegate.h

Index: chrome/browser/api/infobars/confirm_infobar_delegate.h
===================================================================
--- chrome/browser/api/infobars/confirm_infobar_delegate.h	(revision 175396)
+++ chrome/browser/api/infobars/confirm_infobar_delegate.h	(working copy)
@@ -20,6 +20,8 @@
     BUTTON_CANCEL = 1 << 1,
   };
 
+  virtual ~ConfirmInfoBarDelegate();
+
   // Returns the InfoBar type to be displayed for the InfoBar.
   virtual InfoBarAutomationType GetInfoBarAutomationType() const OVERRIDE;
 
@@ -59,7 +61,6 @@
 
  protected:
   explicit ConfirmInfoBarDelegate(InfoBarService* infobar_service);
-  virtual ~ConfirmInfoBarDelegate();
 
   virtual bool ShouldExpireInternal(
       const content::LoadCommittedDetails& details) const OVERRIDE;