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

chrome/browser/ui/media_stream_infobar_delegate.h

Index: chrome/browser/ui/media_stream_infobar_delegate.h
===================================================================
--- chrome/browser/ui/media_stream_infobar_delegate.h	(revision 175396)
+++ chrome/browser/ui/media_stream_infobar_delegate.h	(working copy)
@@ -19,13 +19,17 @@
 // to them.
 class MediaStreamInfoBarDelegate : public ConfirmInfoBarDelegate {
  public:
-  // MediaStreamInfoBarDelegate takes the ownership of the |controller|.
-  MediaStreamInfoBarDelegate(
-      InfoBarService* infobar_service,
-      MediaStreamDevicesController* controller);
-
   virtual ~MediaStreamInfoBarDelegate();
 
+  // Handles a permission request (in |request|) for |web_contents|.  If this
+  // involves prompting the user, creates a media stream delegate, then checks
+  // for an existing infobar for |web_contents| and replaces it if found, or
+  // just adds the new infobar otherwise.  Returns whether an infobar was
+  // created.
+  static bool Create(content::WebContents* web_contents,
+                     const content::MediaStreamRequest& request,
+                     const content::MediaResponseCallback& callback);
+
   // ConfirmInfoBarDelegate:
   virtual void InfoBarDismissed() OVERRIDE;
   virtual gfx::Image* GetIcon() const OVERRIDE;
@@ -39,6 +43,11 @@
   virtual bool LinkClicked(WindowOpenDisposition disposition) OVERRIDE;
 
  private:
+  // MediaStreamInfoBarDelegate takes the ownership of the |controller|.
+  MediaStreamInfoBarDelegate(
+      InfoBarService* infobar_service,
+      MediaStreamDevicesController* controller);
+
   scoped_ptr<MediaStreamDevicesController> controller_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamInfoBarDelegate);