[es6] Unify ArrayBuffer and SharedArrayBuffer constructors.

test/mjsunit/harmony/reflect-get-prototype-of.js

 // Copyright 2010-2015 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 82 matching lines @@
 
 for (var f of errorFunctions) {
   assertPrototypeOf(f, Error);
   assertPrototypeOf(new f(), f.prototype);
 }
 
 
 // Builtin constructors.
 var functions = [
   Array,
-  ArrayBuffer,
   Boolean,
   // DataView,
   Date,
   Error,
   Float32Array,
   Float64Array,
   Function,
   Int16Array,
   Int32Array,
   Int8Array,
@@ skipping 14 matching lines @@
 ];
 
 for (var f of functions) {
   assertPrototypeOf(f, Function.prototype);
   assertPrototypeOf(new f(), f.prototype);
 }
 
 var p = new Promise(function() {});
 assertPrototypeOf(p, Promise.prototype);
 
-var dv = new DataView(new ArrayBuffer());
+var ab = new ArrayBuffer(0);
+assertPrototypeOf(ab, ArrayBuffer.prototype);
+
+var dv = new DataView(ab);
 assertPrototypeOf(dv, DataView.prototype);