Prototype implementation of GET_OWN_PROPERTY intrinsic.

test/mjsunit/getownprivateproperty.js

+// Flags: --allow-natives-syntax
+
+
+var s1 = Symbol("s1");
+var s2 = Symbol("s2");
+
+var p = { xBase : 15 };
+p[s1] = "moo";
+var o = Object.create(p, { x : { value : 25 }});
+o[s2] = "bow-wow"
+
+assertEquals(25, %GET_OWN_PROPERTY(o, "x"));
+assertEquals(undefined, %GET_OWN_PROPERTY(o, "xBase"));
+assertEquals(undefined, %GET_OWN_PROPERTY(o, s1));
+assertEquals("bow-wow", %GET_OWN_PROPERTY(o, s2));
+
+function checkNonOwn(o) {
+  assertEquals(15, o["xBase"]);
+  assertEquals(undefined, %GET_OWN_PROPERTY(o, "xBase"));
+  assertEquals("moo", o[s1]);
+  assertEquals(undefined, %GET_OWN_PROPERTY(o, s1));  
+}
+
+checkNonOwn(o);
+for (var i = 0; i < 1000; i++) {
+  var oNew = Object.create(p);
+  oNew["s" + i] = i;
+  checkNonOwn(oNew);
+}
+