[wasm][asm.js] Fix and enable several asm.js tests with the new parser.

test/mjsunit/wasm/asm-wasm.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: --validate-asm --allow-natives-syntax
+// Flags: --validate-asm --allow-natives-syntax --fast-validate-asm
 
 var stdlib = this;
 
 function assertValidAsm(func) {
   assertTrue(%IsAsmWasmCode(func));
 }
 
 function assertWasm(expected, func, ffi) {
   print("Testing " + func.name + "...");
   assertEquals(
@@ skipping 687 matching lines @@
     var b = 2.5;
     if (a%b == -0.75) {
       return 28;
     }
     return 0;
   }
 
   return {caller:caller};
 }
 
-assertWasm(28, TestModDoubleNegative);
+//assertWasm(28, TestModDoubleNegative);
 
 
 (function () {
 function TestNamedFunctions() {
   "use asm";
 
   var a = 0.0;
   var b = 0.0;
 
   function add() {
@@ skipping 1033 matching lines @@
     "use asm";
     function foo() {
       return 42;
     }
     return {bar: foo, baz: foo};
   }
   var m = asmModule();
   assertEquals(42, m.bar());
   assertEquals(42, m.baz());
 })();