Migrated several tests from blink to V8 repository.

test/webkit/Object-keys.js

Index: test/webkit/Object-keys.js
diff --git a/test/webkit/concat-while-having-a-bad-time.js b/test/webkit/Object-keys.js
similarity index 70%
copy from test/webkit/concat-while-having-a-bad-time.js
copy to test/webkit/Object-keys.js
index dfda1e08a0b36194b787a44ee12a9693acd8aeaf..a8aba48a4ec9c6d60a1ed23553e09b385435e65d 100644
--- a/test/webkit/concat-while-having-a-bad-time.js
+++ b/test/webkit/Object-keys.js
@@ -21,11 +21,16 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-description(
-"Tests the behavior of Array.prototype.concat while the array is having a bad time due to one of the elements we are concatenating."
-);
-
-Object.defineProperty(Array.prototype, 0, { writable: false });
-shouldBe("[42].concat()", "[42]");
-
+description("Test to ensure correct behaviour of Object.keys");
 
+shouldBe("Object.keys({})", "[]");
+shouldBe("Object.keys({a:null})", "['a']");
+shouldBe("Object.keys({a:null, b:null})", "['a', 'b']");
+shouldBe("Object.keys({b:null, a:null})", "['b', 'a']");
+shouldBe("Object.keys([])", "[]");
+shouldBe("Object.keys([null])", "['0']");
+shouldBe("Object.keys([null,null])", "['0','1']");
+shouldBe("Object.keys([null,null,,,,null])", "['0','1','5']");
+shouldBe("Object.keys({__proto__:{a:null}})", "[]");
+shouldBe("Object.keys({__proto__:[1,2,3]})", "[]");
+shouldBe("x=[];x.__proto__=[1,2,3];Object.keys(x)", "[]");