[wasm][asm.js] Make asm.js->wasm return a regular object.

test/mjsunit/asm/asm-validation.js

Index: test/mjsunit/asm/asm-validation.js
diff --git a/test/mjsunit/asm/asm-validation.js b/test/mjsunit/asm/asm-validation.js
index 1f087fc01909827191d0bd23e7a63cbe6aa3f65a..364ecd64d3dd9bd0f233bf917a12beb7aa7657c3 100644
--- a/test/mjsunit/asm/asm-validation.js
+++ b/test/mjsunit/asm/asm-validation.js
@@ -476,3 +476,23 @@ function assertValidAsm(func) {
   Module();
   assertFalse(% IsAsmWasmCode(Module));
 })();
+
+(function TestAsmIsRegular() {
+  function Module() {
+    'use asm';
+    var g = 123;
+    function foo() {
+      return g | 0;
+    }
+    return {x: foo};
+  }
+  var o = Module();
+  assertValidAsm(Module);
+  assertFalse(o instanceof WebAssembly.Instance);
+  assertTrue(o instanceof Object);
+  assertTrue(o.__proto__ === Object.prototype);
+  o.x = 5;
+  assertTrue(typeof o.x === 'number');
+  assertTrue(o.__single_function__ === undefined);
+  assertTrue(o.__foreign_init__ === undefined);
+})();