GuestView: Use Weak Pointers Throughout

chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h

Index: chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h
diff --git a/chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h b/chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h
index 4ddd70e753502bb5c92f2d085646f7b76c6b69a5..667cf73e64669aefda8f031b2854fd73c15f6e5f 100644
--- a/chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h
+++ b/chrome/browser/guest_view/web_view/chrome_web_view_guest_delegate.h
@@ -88,6 +88,10 @@ class ChromeWebViewGuestDelegate : public extensions::WebViewGuestDelegate,
 
   extensions::WebViewGuest* const web_view_guest_;
 
+  // This is used to ensure pending tasks will not fire after this object is
+  // destroyed.
+  base::WeakPtrFactory<ChromeWebViewGuestDelegate> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(ChromeWebViewGuestDelegate);
 };