Use the loading task runner for mojo-loading

content/child/url_loader_client_impl.cc

Index: content/child/url_loader_client_impl.cc
diff --git a/content/child/url_loader_client_impl.cc b/content/child/url_loader_client_impl.cc
index ab1e9309d93cd8d06da954d90ae32d3abfb859ef..0ade2475acf9b8d052fbf54f2c23c2103a83df22 100644
--- a/content/child/url_loader_client_impl.cc
+++ b/content/child/url_loader_client_impl.cc
@@ -30,6 +30,8 @@ URLLoaderClientImpl::~URLLoaderClientImpl() {
 
 void URLLoaderClientImpl::Bind(
     mojom::URLLoaderClientAssociatedPtrInfo* client_ptr_info) {
+  // TODO(yhirano): Use |task_runner_| here.
+  // Currently it is unable because of a ChannelAssociatedInterface restriction.
   binding_.Bind(client_ptr_info);
 }