Check crate root for docs in missing_doc lint.

Because the root module isn't actually an item, we need to do some hackish
handling of it.

Closes #10656.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index f19a99ffcee..985dcd27271 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -130,6 +130,7 @@ pub fn walk_mod<E:Clone, V:Visitor<E>>(visitor: &mut V, module: &_mod, env: E) {
     for view_item in module.view_items.iter() {
         visitor.visit_view_item(view_item, env.clone())
     }
+
     for item in module.items.iter() {
         visitor.visit_item(*item, env.clone())
     }