Editorial: Clean up StringGetOwnProperty (#3523)

Remove a redundant check and swap comparison operands for a more conventional ordering.

Author: gibson042

spec.html

@@ -14430,13 +14430,12 @@ <h1>
         <emu-alg>
           1. If _P_ is not a String, return *undefined*.
           1. Let _index_ be CanonicalNumericIndexString(_P_).
-          1. If _index_ is *undefined*, return *undefined*.
           1. If _index_ is not an integral Number, return *undefined*.
           1. If _index_ is *-0*<sub>𝔽</sub> or _index_ &lt; *-0*<sub>𝔽</sub>, return *undefined*.
           1. Let _str_ be _S_.[[StringData]].
           1. Assert: _str_ is a String.
           1. Let _len_ be the length of _str_.
-          1. If _len_ ≤ ℝ(_index_), return *undefined*.
+          1. If ℝ(_index_) ≥ _len_, return *undefined*.
           1. Let _resultStr_ be the substring of _str_ from ℝ(_index_) to ℝ(_index_) + 1.
           1. Return the PropertyDescriptor { [[Value]]: _resultStr_, [[Writable]]: *false*, [[Enumerable]]: *true*, [[Configurable]]: *false* }.
         </emu-alg>