Enable large object space for command line runs.

Added a dynamic large_object_threshold_ variable which is max int
when the large object space is disabled.

No longer clear timing logger timings after zygote creation since
it is not required and removes the boot semispace timings.

Change-Id: I693865f4699cc32381199377239854c6ec42f37e
diff --git a/runtime/gc/heap-inl.h b/runtime/gc/heap-inl.h
index e089ef2..89ded0b 100644
--- a/runtime/gc/heap-inl.h
+++ b/runtime/gc/heap-inl.h
@@ -256,7 +256,7 @@
   // Zygote resulting in it being prematurely freed.
   // We can only do this for primitive objects since large objects will not be within the card table
   // range. This also means that we rely on SetClass not dirtying the object's card.
-  return byte_count >= kLargeObjectThreshold && have_zygote_space_ && c->IsPrimitiveArray();
+  return byte_count >= large_object_threshold_ && c->IsPrimitiveArray();
 }
 
 template <bool kGrow>