Refactor GuestView construction

chrome/browser/guest_view/guest_view.h

Index: chrome/browser/guest_view/guest_view.h
diff --git a/chrome/browser/guest_view/guest_view.h b/chrome/browser/guest_view/guest_view.h
index 41612e44d30e812acbd40c0138ef1a7aacf9063d..b4435001f730d327184b70d692789530133e7d1e 100644
--- a/chrome/browser/guest_view/guest_view.h
+++ b/chrome/browser/guest_view/guest_view.h
@@ -5,6 +5,7 @@
 #ifndef CHROME_BROWSER_GUEST_VIEW_GUEST_VIEW_H_
 #define CHROME_BROWSER_GUEST_VIEW_GUEST_VIEW_H_
 
+#include "base/bind.h"
 #include "chrome/browser/guest_view/guest_view_base.h"
 #include "content/public/browser/render_frame_host.h"
 
@@ -14,6 +15,10 @@
 template <typename T>
 class GuestView : public GuestViewBase {
  public:
+  static void Register() {
+    GuestViewBase::RegisterGuestViewType(T::Type, base::Bind(&T::Create));
+  }
+
   static T* From(int embedder_process_id, int guest_instance_id) {
     GuestViewBase* guest =
         GuestViewBase::From(embedder_process_id, guest_instance_id);