Aesthetic changes in art::mirror::Object and art::mirror::Class.

Test: mmma art
Change-Id: I1c7bf2e3b0420238ee2ae249aca9b7fce492a3e6
diff --git a/runtime/mirror/class.cc b/runtime/mirror/class.cc
index e6bfe55..81b96e1 100644
--- a/runtime/mirror/class.cc
+++ b/runtime/mirror/class.cc
@@ -1251,7 +1251,7 @@
 
 uint32_t Class::Depth() {
   uint32_t depth = 0;
-  for (ObjPtr<Class> klass = this; klass->GetSuperClass() != nullptr; klass = klass->GetSuperClass()) {
+  for (ObjPtr<Class> cls = this; cls->GetSuperClass() != nullptr; cls = cls->GetSuperClass()) {
     depth++;
   }
   return depth;