rollup merge of #20279: dgiagio/libserialize_deprecated_fix1

Fixes #20278

diff --combined src/libserialize/json.rs
index e95f87ccb89fc29a89f9f7928df414df26b469a3,aeb384f464d07c9c87938740e198a2aa16dea97d..3f0d59c319a69e7e44165573b698555b101129d5
--- 1/src/libserialize/json.rs
--- 2/src/libserialize/json.rs
+++ b/src/libserialize/json.rs
@@@ -29,7 -29,7 +29,7 @@@
  //! * `String`: equivalent to rust's `String`
  //! * `Array`: equivalent to rust's `Vec<T>`, but also allowing objects of different types in the
  //!   same array
 -//! * `Object`: equivalent to rust's `Treemap<String, json::Json>`
 +//! * `Object`: equivalent to rust's `BTreeMap<String, json::Json>`
  //! * `Null`
  //!
  //! An object is a series of string keys mapping to values, in `"key": value` format.
@@@ -2517,7 -2517,7 +2517,7 @@@ mod tests 
      #[test]
      fn test_from_str_trait() {
          let s = "null";
-         assert!(::std::str::from_str::<Json>(s).unwrap() == from_str(s).unwrap());
+         assert!(s.parse::<Json>().unwrap() == s.parse().unwrap());
      }
  
      #[test]
@@@ -3729,8 -3729,8 +3729,8 @@@
          let array3 = Array(vec!(U64(1), U64(2), U64(3)));
          let object = {
              let mut tree_map = BTreeMap::new();
-             tree_map.insert("a".into_string(), U64(1));
-             tree_map.insert("b".into_string(), U64(2));
+             tree_map.insert("a".to_string(), U64(1));
+             tree_map.insert("b".to_string(), U64(2));
              Object(tree_map)
          };
  
@@@ -3762,8 -3762,8 +3762,8 @@@
          assert_eq!((vec![1u, 2]).to_json(), array2);
          assert_eq!(vec!(1u, 2, 3).to_json(), array3);
          let mut tree_map = BTreeMap::new();
-         tree_map.insert("a".into_string(), 1u);
-         tree_map.insert("b".into_string(), 2);
+         tree_map.insert("a".to_string(), 1u);
+         tree_map.insert("b".to_string(), 2);
          assert_eq!(tree_map.to_json(), object);
          let mut hash_map = HashMap::new();
          hash_map.insert("a".to_string(), 1u);