Make our tests only 2x slower than they were this morning...

...by disabling the expensive heap checks that made us 6x slower.

Change-Id: I049db7ab256214b79d67586e1f70bbf7a1936608
diff --git a/src/common_test.h b/src/common_test.h
index 5318008..5943714 100644
--- a/src/common_test.h
+++ b/src/common_test.h
@@ -90,6 +90,7 @@
     ASSERT_TRUE(runtime_.get() != NULL);
     class_linker_ = runtime_->GetClassLinker();
 
+    //Heap::DisableObjectValidation();
     Heap::VerifyHeap();  // Check for heap corruption before the test
   }