Remove runtime flags for sloppy mode block scoping features

test/mjsunit/es6/block-sloppy-function.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-sloppy --harmony-sloppy-let
-// Flags: --harmony-sloppy-function
-
 // Test Annex B 3.3 semantics for functions declared in blocks in sloppy mode.
 // http://www.ecma-international.org/ecma-262/6.0/#sec-block-level-function-declarations-web-legacy-compatibility-semantics
 
 (function overridingLocalFunction() {
   var x = [];
   assertEquals('function', typeof f);
   function f() {
     x.push(1);
   }
   f();
@@ skipping 274 matching lines @@
 throws = false;
 try {
   eval('{ function hoistWhenFrozen() {} }');
 } catch (e) {
   throws = true;
 }
 assertFalse(this.hasOwnProperty("hoistWhenFrozen"));
 assertThrows(() => hoistWhenFrozen, ReferenceError);
 // Should be assertFalse BUG(v8:4452)
 assertTrue(throws);