8325189: Enable this-escape javac warning in java.base

Reviewed-by: alanb, erikj, naoto, smarks, ihse, joehw, lancea, weijun

src/java.base/share/classes/java/util/HashMap.java

@@ -487,6 +487,7 @@ public class HashMap<K,V> extends AbstractMap<K,V>
      * @param   m the map whose mappings are to be placed in this map
      * @throws  NullPointerException if the specified map is null
      */
+    @SuppressWarnings("this-escape")
     public HashMap(Map<? extends K, ? extends V> m) {
         this.loadFactor = DEFAULT_LOAD_FACTOR;
         putMapEntries(m, false);