rustdoc: add another test case for glob shadowing

src/test/rustdoc/glob-shadowing-const.rs

@@ -0,0 +1,20 @@
+// https://github.com/rust-lang/rust/pull/83872#issuecomment-820101008
+#![crate_name="foo"]
+
+mod sub4 {
+    /// 0
+    pub const X: usize = 0;
+    pub mod inner {
+        pub use super::*;
+        /// 1
+        pub const X: usize = 1;
+    }
+}
+
+#[doc(inline)]
+pub use sub4::inner::*;
+
+// @has 'foo/index.html'
+// @has - '//div[@class="item-right docblock-short"]' '1'
+// @!has - '//div[@class="item-right docblock-short"]' '0'
+fn main() { assert_eq!(X, 1); }