Revert of Add web compat workarounds for ES2015 RegExp semantics

test/mjsunit/es6/regexp-flags.js

Index: test/mjsunit/es6/regexp-flags.js
diff --git a/test/mjsunit/es6/regexp-flags.js b/test/mjsunit/es6/regexp-flags.js
index 2f1222197dc8905472084d259188e6daa5145b28..98070fb7352766a8ab02136f2ca3868c14deee9c 100644
--- a/test/mjsunit/es6/regexp-flags.js
+++ b/test/mjsunit/es6/regexp-flags.js
@@ -50,11 +50,7 @@
 
 
 function testName(name) {
-  if (name === "sticky") {
-    assertEquals(undefined, RegExp.prototype[name]);
-  } else {
-    assertThrows(() => RegExp.prototype[name], TypeError);
-  }
+  assertThrows(() => RegExp.prototype[name], TypeError);
   assertEquals(
       "get " + name,
       Object.getOwnPropertyDescriptor(RegExp.prototype, name).get.name);