Implement Object.clone.

Also add a conditional to Thread to keep tests running.

Change-Id: I02145973af0fca823acb689e04912c2020d9c650
diff --git a/src/object_test.cc b/src/object_test.cc
index 9b6897d..7f6ad4c 100644
--- a/src/object_test.cc
+++ b/src/object_test.cc
@@ -53,6 +53,14 @@
                                       String::AllocFromModifiedUtf8("Ljava/lang/reflect/Method;")));
 }
 
+TEST_F(ObjectTest, Clone) {
+  ObjectArray<Object>* a1 = class_linker_->AllocObjectArray<Object>(256);
+  size_t s1 = a1->SizeOf();
+  Object* clone = a1->Clone();
+  EXPECT_EQ(s1, clone->SizeOf());
+  EXPECT_TRUE(clone->GetClass() == a1->GetClass());
+}
+
 TEST_F(ObjectTest, AllocObjectArray) {
   ObjectArray<Object>* oa = class_linker_->AllocObjectArray<Object>(2);
   EXPECT_EQ(2, oa->GetLength());