Remove usage of S.p.charCodeAt from uri.js

test/mjsunit/uri.js

Index: test/mjsunit/uri.js
diff --git a/test/mjsunit/uri.js b/test/mjsunit/uri.js
index fae349f439faf84fa43a997e7f8f0eec738ca547..862e420f892473c7465b1822f860d49f49e92ace 100644
--- a/test/mjsunit/uri.js
+++ b/test/mjsunit/uri.js
@@ -88,3 +88,13 @@ test("\u1234\u0123\uabcd");
 test("abcd");
 test("ab<\u1234\u0123");
 test("ab\u1234<\u0123");
+
+
+(function TestDeleteCharCodeAt() {
+  assertEquals('abc', encodeURI('abc'));
+  assertEquals('abc', decodeURI('abc'));
+  assertTrue(delete String.prototype.charCodeAt);
+  assertTrue(delete String.prototype.charAt);
+  assertEquals('abc', encodeURI('abc'));
+  assertEquals('abc', decodeURI('abc'));
+})();