Use non volatile lock words in semispace collector.

GSS FormulaEvaluationActions.EvaluateAndApplyChanges:
Before GC time: 9.1s
After GC time: 7.98s

Fixed timing logger errors.

Change-Id: I4193c6ccbbbe7a7220dfaabbf3472a5dcebae616
diff --git a/compiler/image_test.cc b/compiler/image_test.cc
index 05d6693..7c5741b 100644
--- a/compiler/image_test.cc
+++ b/compiler/image_test.cc
@@ -164,7 +164,7 @@
       EXPECT_TRUE(reinterpret_cast<byte*>(klass) >= image_end ||
                   reinterpret_cast<byte*>(klass) < image_begin) << descriptor;
     }
-    EXPECT_TRUE(Monitor::IsValidLockWord(klass->GetLockWord()));
+    EXPECT_TRUE(Monitor::IsValidLockWord(klass->GetLockWord(false)));
   }
 }