Use a resource throttle to implement shouldOverrideUrlLoading.

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index 99f120c9f833c3c3788ab417233ffd0d58ab20aa..aaabed84eced74bb8b8de8d0918bb6cafbad644d 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -771,12 +771,14 @@ void RenderFrameHostImpl::OnDidFailProvisionalLoadWithError(
 void RenderFrameHostImpl::OnDidFailLoadWithError(
     const GURL& url,
     int error_code,
-    const base::string16& error_description) {
+    const base::string16& error_description,
+    bool was_ignored_by_handler) {
   GURL validated_url(url);
   GetProcess()->FilterURL(false, &validated_url);
 
   frame_tree_node_->navigator()->DidFailLoadWithError(
-      this, validated_url, error_code, error_description);
+      this, validated_url, error_code, error_description,
+      was_ignored_by_handler);
 }
 
 // Called when the renderer navigates.  For every frame loaded, we'll get this