[asm] Fix lots of invalid asm.js tests

test/mjsunit/asm/float32array-outofbounds.js

 // Copyright 2014 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.
 
 function Module(stdlib, foreign, heap) {
   "use asm";
   var MEM32 = new stdlib.Float32Array(heap);
   function load(i) {
     i = i|0;
-    i = +MEM32[i >> 2];
-    return i;
+    return +MEM32[i >> 2];
   }
   function store(i, v) {
     i = i|0;
     v = +v;
     MEM32[i >> 2] = v;
   }
   return { load: load, store: store };
 }
 
 var m = Module(this, {}, new ArrayBuffer(4));
 
 m.store(0, 42.0);
 for (var i = 1; i < 64; ++i) {
   m.store(i * 4 * 32 * 1024, i);
 }
 assertEquals(42.0, m.load(0));
 for (var i = 1; i < 64; ++i) {
   assertEquals(NaN, m.load(i * 4 * 32 * 1024));
 }