Resolve visibility paths as modules not as types.

tests/ui/resolve/unresolved-segments-visibility.rs

@@ -0,0 +1,11 @@
+// Check that we do not ICE due to unresolved segments in visibility path.
+#![crate_type = "lib"]
+
+extern crate alloc as b;
+
+mod foo {
+    mod bar {
+        pub(in b::string::String::newy) extern crate alloc as e;
+        //~^ ERROR failed to resolve: `String` is a struct, not a module [E0433]
+    }
+}