Update to Chromium revision 304f01a1 (#358063)

- Improve ordering of CefLoadHandler callbacks. OnLoadingStateChange will
  be called before and after all calls to OnLoadStart and OnLoadEnd.
  OnLoadStart/OnLoadEnd calls will occur as matching pairs
  (see http://crbug.com/539952#c2).
- Remove the |requesting_url| argument to CefGeolocationHandler::
  OnCancelGeolocationPermission. Clients can use the |request_id| argument
  to track this information themselves.
- Fix a crash when loading the PDF extension in multiple browsers with a
  custom CefRequestContext (issue #1757).

libcef/browser/cookie_manager_impl.cc

@@ -556,6 +556,7 @@ void CefCookieManagerImpl::SetCookieInternal(
       cookie.secure ? true : false,
       cookie.httponly ? true : false,
       false,  // First-party only.
+      false,  // Enforces prefixes.
       net::COOKIE_PRIORITY_DEFAULT,
       base::Bind(SetCookieCallbackImpl, callback));
 }