Add a NavigationThrottle to the public content/ interface

content/browser/loader/navigation_url_loader_impl_core.cc

Index: content/browser/loader/navigation_url_loader_impl_core.cc
diff --git a/content/browser/loader/navigation_url_loader_impl_core.cc b/content/browser/loader/navigation_url_loader_impl_core.cc
index 7cbf6999946551028e17f588a2d5277e81119cff..0cb9ca561541aa067fbb61ed98c30c683f4cad22 100644
--- a/content/browser/loader/navigation_url_loader_impl_core.cc
+++ b/content/browser/loader/navigation_url_loader_impl_core.cc
@@ -58,10 +58,10 @@ void NavigationURLLoaderImplCore::FollowRedirect() {
     resource_handler_->FollowRedirect();
 }
 
-
 void NavigationURLLoaderImplCore::NotifyRequestRedirected(
     const net::RedirectInfo& redirect_info,
-    ResourceResponse* response) {
+    ResourceResponse* response,
+    bool is_external_protocol) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   // Make a copy of the ResourceResponse before it is passed to another thread.
@@ -72,7 +72,7 @@ void NavigationURLLoaderImplCore::NotifyRequestRedirected(
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&NavigationURLLoaderImpl::NotifyRequestRedirected, loader_,
-                 redirect_info, response->DeepCopy()));
+                 redirect_info, response->DeepCopy(), is_external_protocol));
 }
 
 void NavigationURLLoaderImplCore::NotifyResponseStarted(