[es6] Initial support for let/const bindings in sloppy mode

test/mjsunit/harmony/block-const-assign-sloppy.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Flags: --harmony-computed-property-names
+// Flags: --no-legacy-const --harmony-sloppy
 
 // Test that we throw early syntax errors in harmony mode
 // when using an immutable binding in an assigment or with
 // prefix/postfix decrement/increment operators.
 
-"use strict";
-
 const decls = [
   // Const declaration.
   function(use) { return "const c = 1; " + use + ";" }, TypeError,
   function(use) { return "const x = 0, c = 1; " + use + ";" }, TypeError,
   function(use) { return "const c = 1, x = (" + use + ");" }, TypeError,
   function(use) { return use + "; const c = 1;" }, ReferenceError,
   function(use) { return use + "; const x = 0, c = 1;" }, ReferenceError,
   function(use) { return "const x = (" + use + "), c = 1;" }, ReferenceError,
   function(use) { return "const c = (" + use + ");" }, ReferenceError,
 
@@ skipping 105 matching lines @@
 
 for (var d = 0; d < decls.length; d += 2) {
   for (var u = 0; u < uses.length; ++u) {
     for (var o = 0; o < declcontexts.length; ++o) {
       for (var i = 0; i < usecontexts.length; ++i) {
         Test(declcontexts[o](decls[d](usecontexts[i](uses[u]))), decls[d + 1]);
       }
     }
   }
 }