ART: Add object-readbarrier-inl.h

Move some read-barrier code into a new header. This prunes the
include tree for the concurrent-copying collector. Clean up other
related includes.

Test: mmma art
Change-Id: I40ce4e74f2e5d4c692529ffb4df933230b6fd73e
diff --git a/runtime/class_table.cc b/runtime/class_table.cc
index 374b711..0891d3f 100644
--- a/runtime/class_table.cc
+++ b/runtime/class_table.cc
@@ -17,6 +17,7 @@
 #include "class_table.h"
 
 #include "mirror/class-inl.h"
+#include "oat_file.h"
 
 namespace art {