Enable compiling mjsunit tests as ES6 modules

test/mjsunit/harmony/module-parsing-eval.js

 // Copyright 2012 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 21 matching lines @@
 assertThrows("import x from 'http://url';", SyntaxError);
 
 assertThrows("{ export let x; }", SyntaxError);
 assertThrows("{ import x from 'http://url'; }", SyntaxError);
 
 assertThrows("function f() { export let x; }", SyntaxError);
 assertThrows("function f() { import x from 'http://url'; }", SyntaxError);
 
 assertThrows("function f() { { export let x; } }", SyntaxError);
 assertThrows("function f() { { import x from 'http://url'; } }", SyntaxError);