Make out arguments non-reference types.

Also, tidy some portable related code.

Change-Id: I67c8aa52eef8b556ca117ecda1b1e75465ba06a5
diff --git a/compiler/common_compiler_test.h b/compiler/common_compiler_test.h
index 9bcc040..d034b79 100644
--- a/compiler/common_compiler_test.h
+++ b/compiler/common_compiler_test.h
@@ -353,7 +353,7 @@
     CHECK(method != nullptr);
     TimingLogger timings("CommonTest::CompileMethod", false, false);
     timings.StartSplit("CompileOne");
-    compiler_driver_->CompileOne(method, timings);
+    compiler_driver_->CompileOne(method, &timings);
     MakeExecutable(method);
     timings.EndSplit();
   }