Allow parameterless typed array constructors.

ES6 spec tacitly allows them, and they are allowed in Firefox and in
WebKit/Blink.

R=bmeurer@chromium.org,rossberg@chromium.org

Review URL: https://codereview.chromium.org/18769005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15579 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/messages.js

@@ -104,8 +104,6 @@ var kMessages = {
   observe_perform_non_function:  ["Cannot perform non-function"],
   observe_notify_non_notifier:   ["notify called on non-notifier object"],
   proto_poison_pill:             ["Generic use of __proto__ accessor not allowed"],
-  parameterless_typed_array_constr:
-                                 ["%0"," constructor should have at least one argument."],
   not_typed_array:               ["this is not a typed array."],
   invalid_argument:              ["invalid_argument"],
   data_view_not_array_buffer:    ["First argument to DataView constructor must be an ArrayBuffer"],

src/typedarray.js

@@ -89,12 +89,11 @@ function CreateTypedArrayConstructor(name, elementSize, arrayId, constructor) {
     if (%_IsConstructCall()) {
       if (IS_ARRAYBUFFER(arg1)) {
         ConstructByArrayBuffer(this, arg1, arg2, arg3);
-      } else if (IS_NUMBER(arg1) || IS_STRING(arg1) || IS_BOOLEAN(arg1)) {
+      } else if (IS_NUMBER(arg1) || IS_STRING(arg1) ||
+                 IS_BOOLEAN(arg1) || IS_UNDEFINED(arg1)) {
         ConstructByLength(this, arg1);
-      } else if (!IS_UNDEFINED(arg1)){
-        ConstructByArrayLike(this, arg1);
       } else {
-        throw MakeTypeError("parameterless_typed_array_constr", [name]);
+        ConstructByArrayLike(this, arg1);
       }
     } else {
       throw MakeTypeError("constructor_not_function", [name])

test/mjsunit/harmony/typedarrays.js

@@ -219,7 +219,6 @@ function TestTypedArray(proto, elementSize, typicalElement) {
     assertThrows(function() { new proto(unalignedArrayBuffer)}, RangeError);
     assertThrows(function() { new proto(unalignedArrayBuffer, 5*elementSize)},
                  RangeError);
-    assertThrows(function() { new proto() }, TypeError);
   }
 
   var aFromString = new proto("30");
@@ -250,6 +249,12 @@ function TestTypedArray(proto, elementSize, typicalElement) {
   assertSame(0, aOverAbLen0.length);
   assertSame(0, aOverAbLen0.byteLength);
   assertSame(0, aOverAbLen0.byteOffset);
+
+  var aNoParam = new proto();
+  assertSame(elementSize, aNoParam.BYTES_PER_ELEMENT);
+  assertSame(0, aNoParam.length);
+  assertSame(0, aNoParam.byteLength);
+  assertSame(0, aNoParam.byteOffset);
 }
 
 TestTypedArray(Uint8Array, 1, 0xFF);