[wasm] Add a magic word and a version number to the binary.

test/mjsunit/wasm/indirect-calls.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: --expose-wasm
 
 load("test/mjsunit/wasm/wasm-constants.js");
 
 var module = (function () {
   var kFuncWithBody = 9;
   var kFuncImported = 7;
   var kBodySize1 = 5;
   var kBodySize2 = 8;
   var kFuncTableSize = 8;
-  var kSubOffset = 13 + kFuncWithBody + kBodySize1 + kFuncImported + kFuncWithBody + kBodySize2 + kFuncTableSize + 1;
+  var kSubOffset = kHeaderSize + 13 + kFuncWithBody + kBodySize1 + kFuncImported + kFuncWithBody + kBodySize2 + kFuncTableSize + 1;
   var kAddOffset = kSubOffset + 4;
   var kMainOffset = kAddOffset + 4;
 
   var ffi = new Object();
   ffi.add = (function(a, b) { return a + b | 0; });
 
-  return _WASMEXP_.instantiateModule(bytes(
+  return _WASMEXP_.instantiateModule(bytesWithHeader(
     // -- signatures
     kDeclSignatures, 2,
     2, kAstI32, kAstI32, kAstI32, // int, int -> int
     3, kAstI32, kAstI32, kAstI32, kAstI32, // int, int, int -> int
     // -- function #0 (sub)
     kDeclFunctions, 3,
     kDeclFunctionName,
     0, 0,                         // signature offset
     kSubOffset, 0, 0, 0,          // name offset
     kBodySize1, 0,                // body size
@@ skipping 31 matching lines @@
 assertFalse(module === null);
 assertFalse(module === 0);
 assertEquals("object", typeof module);
 assertEquals("function", typeof module.main);
 
 assertEquals(5, module.main(0, 12, 7));
 assertEquals(19, module.main(1, 12, 7));
 
 assertTraps(kTrapFuncSigMismatch, "module.main(2, 12, 33)");
 assertTraps(kTrapFuncInvalid, "module.main(3, 12, 33)");