Move most of runtime/base to libartbase/base

Enforce the layering that code in runtime/base should not depend on
runtime by separating it into libartbase.  Some of the code in
runtime/base depends on the Runtime class, so it cannot be moved yet.
Also, some of the tests depend on CommonRuntimeTest, which itself needs
to be factored (in a subsequent CL).

Bug: 22322814
Test: make -j 50 checkbuild
      make -j 50 test-art-host

Change-Id: I8b096c1e2542f829eb456b4b057c71421b77d7e2
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index 6000317..ea06567 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -21,6 +21,8 @@
 #include "base/casts.h"
 #include "base/enums.h"
 #include "base/iteration_range.h"
+#include "base/stride_iterator.h"
+#include "base/utils.h"
 #include "class_flags.h"
 #include "class_status.h"
 #include "dex/dex_file.h"
@@ -33,9 +35,7 @@
 #include "object.h"
 #include "object_array.h"
 #include "read_barrier_option.h"
-#include "stride_iterator.h"
 #include "thread.h"
-#include "utils.h"
 
 namespace art {