Drop obsolete ES6 TODOs about activating extended mode.

test/mjsunit/harmony/block-let-declaration.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
@@ skipping 10 matching lines @@
 // 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-scoping
 
 // Test let declarations in various settings.
-// TODO(ES6): properly activate extended mode
+
 "use strict";
 
 // Global
 let x;
 let y = 2;
 const z = 4;
 
 // Block local
 {
   let y;
@@ skipping 86 matching lines @@
 
 // Test function declarations in statement position in strict mode.
 TestLocalThrows("function f() { if (true) function g() {}", SyntaxError);
 TestLocalThrows("function f() { if (true) {} else function g() {}", SyntaxError);
 TestLocalThrows("function f() { do function g() {} while (false)", SyntaxError);
 TestLocalThrows("function f() { while (false) function g() {}", SyntaxError);
 TestLocalThrows("function f() { label: function g() {}", SyntaxError);
 TestLocalThrows("function f() { for (;false;) function g() {}", SyntaxError);
 TestLocalThrows("function f() { switch (true) { case true: function g() {} }", SyntaxError);
 TestLocalThrows("function f() { switch (true) { default: function g() {} }", SyntaxError);