Remove redundant code in NavigationHandleImpl constructor.

Removes some redundant code that appears to have been as
accidentally introduced by
https://chromium-review.googlesource.com/c/chromium/src/+/1409551

Change-Id: I784b6cb91f788dfc2e2c8bd3b1e888e8b54699b2
Reviewed-on: https://chromium-review.googlesource.com/c/1433144Reviewed-by: Camille Lamy <clamy@chromium.org>
Commit-Queue: Aaron Colwell <acolwell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#626282}

content/browser/frame_host/navigation_handle_impl.cc

@@ -199,14 +199,6 @@ NavigationHandleImpl::NavigationHandleImpl(
   DCHECK(!navigation_start.is_null());
   DCHECK(!IsRendererDebugURL(url));
 
-  site_url_ = SiteInstance::GetSiteForURL(frame_tree_node()
-                                              ->current_frame_host()
-                                              ->GetSiteInstance()
-                                              ->GetBrowserContext(),
-                                          url_);
-  if (redirect_chain_.empty())
-    redirect_chain_.push_back(url);
-
   starting_site_instance_ =
       frame_tree_node()->current_frame_host()->GetSiteInstance();