Allow URLRequests from one context to have different NetworkDelegates.

net/url_request/url_request_context.cc

Index: net/url_request/url_request_context.cc
diff --git a/net/url_request/url_request_context.cc b/net/url_request/url_request_context.cc
index 7f4e7996ed64363690d3674817a08f982a64c20f..aa3ec913f4a4b3030e6ae39038e8eae2c479bc87 100644
--- a/net/url_request/url_request_context.cc
+++ b/net/url_request/url_request_context.cc
@@ -78,7 +78,8 @@ scoped_ptr<URLRequest> URLRequestContext::CreateRequest(
     URLRequest::Delegate* delegate,
     CookieStore* cookie_store) const {
   return scoped_ptr<URLRequest>(
-      new URLRequest(url, priority, delegate, this, cookie_store));
+      new URLRequest(url, priority, delegate, this, cookie_store,
+                     network_delegate_));
 }
 
 void URLRequestContext::set_cookie_store(CookieStore* cookie_store) {