Revert of [es6] Correctify and unify ArrayBuffer and SharedArrayBuffer constructors.

src/js/harmony-sharedarraybuffer.js

Index: src/js/harmony-sharedarraybuffer.js
diff --git a/src/js/harmony-sharedarraybuffer.js b/src/js/harmony-sharedarraybuffer.js
index 10ceb70d27b739d434eb3dc1c5f88755a81ddfbb..37480617b51c7bea70c14e3f3ea1140e0f9cc51b 100644
--- a/src/js/harmony-sharedarraybuffer.js
+++ b/src/js/harmony-sharedarraybuffer.js
@@ -9,13 +9,26 @@
 %CheckIsBootstrapping();
 
 var GlobalSharedArrayBuffer = global.SharedArrayBuffer;
+var GlobalObject = global.Object;
 var MakeTypeError;
+var ToPositiveInteger;
+var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   MakeTypeError = from.MakeTypeError;
+  ToPositiveInteger = from.ToPositiveInteger;
 })
 
 // -------------------------------------------------------------------
+
+function SharedArrayBufferConstructor(length) { // length = 1
+  if (!IS_UNDEFINED(new.target)) {
+    var byteLength = ToPositiveInteger(length, kInvalidArrayBufferLength);
+    %ArrayBufferInitialize(this, byteLength, kShared);
+  } else {
+    throw MakeTypeError(kConstructorNotFunction, "SharedArrayBuffer");
+  }
+}
 
 function SharedArrayBufferGetByteLen() {
   if (!IS_SHAREDARRAYBUFFER(this)) {
@@ -25,7 +38,27 @@
   return %_ArrayBufferGetByteLength(this);
 }
 
+function SharedArrayBufferIsViewJS(obj) {
+  return %ArrayBufferIsView(obj);
+}
+
+
+// Set up the SharedArrayBuffer constructor function.
+%SetCode(GlobalSharedArrayBuffer, SharedArrayBufferConstructor);
+%FunctionSetPrototype(GlobalSharedArrayBuffer, new GlobalObject());
+
+// Set up the constructor property on the SharedArrayBuffer prototype object.
+%AddNamedProperty(GlobalSharedArrayBuffer.prototype, "constructor",
+                  GlobalSharedArrayBuffer, DONT_ENUM);
+
+%AddNamedProperty(GlobalSharedArrayBuffer.prototype,
+    toStringTagSymbol, "SharedArrayBuffer", DONT_ENUM | READ_ONLY);
+
 utils.InstallGetter(GlobalSharedArrayBuffer.prototype, "byteLength",
                     SharedArrayBufferGetByteLen);
 
+utils.InstallFunctions(GlobalSharedArrayBuffer, DONT_ENUM, [
+    "isView", SharedArrayBufferIsViewJS
+]);
+
 })