Add GetPropertyAttribute method for Object in the API

test/cctest/test-api.cc

Index: test/cctest/test-api.cc
diff --git a/test/cctest/test-api.cc b/test/cctest/test-api.cc
index 1531f905d1b078f6286418e3c0096e98350a8a66..075f9ac7f73277a092a2105b09e8d5e02d23f089 100644
--- a/test/cctest/test-api.cc
+++ b/test/cctest/test-api.cc
@@ -2048,10 +2048,15 @@ THREADED_TEST(GetSetProperty) {
 THREADED_TEST(PropertyAttributes) {
   v8::HandleScope scope;
   LocalContext context;
+  // none
+  Local<String> prop = v8_str("none");
+  context->Global()->Set(prop, v8_num(7));
+  CHECK_EQ(v8::None, context->Global()->GetPropertyAttribute(prop));
   // read-only
-  Local<String> prop = v8_str("read_only");
+  prop = v8_str("read_only");
   context->Global()->Set(prop, v8_num(7), v8::ReadOnly);
   CHECK_EQ(7, context->Global()->Get(prop)->Int32Value());
+  CHECK_EQ(v8::ReadOnly, context->Global()->GetPropertyAttribute(prop));
   Script::Compile(v8_str("read_only = 9"))->Run();
   CHECK_EQ(7, context->Global()->Get(prop)->Int32Value());
   context->Global()->Set(prop, v8_num(10));
@@ -2062,6 +2067,11 @@ THREADED_TEST(PropertyAttributes) {
   CHECK_EQ(13, context->Global()->Get(prop)->Int32Value());
   Script::Compile(v8_str("delete dont_delete"))->Run();
   CHECK_EQ(13, context->Global()->Get(prop)->Int32Value());
+  CHECK_EQ(v8::DontDelete, context->Global()->GetPropertyAttribute(prop));
+  // dont-enum
+  prop = v8_str("dont_enum");
+  context->Global()->Set(prop, v8_num(28), v8::DontEnum);
+  CHECK_EQ(v8::DontEnum, context->Global()->GetPropertyAttribute(prop));
 }