Document charCodeAt edge case behavior in first line (#63344)

Author: bwalter007

src/lib/es5.d.ts

@@ -400,8 +400,8 @@ interface String {
     charAt(pos: number): string;
 
     /**
-     * Returns the Unicode value of the character at the specified location.
-     * @param index The zero-based index of the desired character. If there is no character at the specified index, NaN is returned.
+     * Returns the Unicode value of the character at the specified location, or NaN if the index is out of bounds.
+     * @param index The zero-based index of the desired character.
      */
     charCodeAt(index: number): number;
 

tests/baselines/reference/completionsStringMethods.baseline

@@ -209,7 +209,7 @@
           ],
           "documentation": [
             {
-              "text": "Returns the Unicode value of the character at the specified location.",
+              "text": "Returns the Unicode value of the character at the specified location, or NaN if the index is out of bounds.",
               "kind": "text"
             }
           ],
@@ -226,7 +226,7 @@
                   "kind": "space"
                 },
                 {
-                  "text": "The zero-based index of the desired character. If there is no character at the specified index, NaN is returned.",
+                  "text": "The zero-based index of the desired character.",
                   "kind": "text"
                 }
               ]