Move ArrayRef to runtime/base

Will be used in upcoming CLs regarding VDEX and VerifierDeps.

Test: m test-art-host
Change-Id: I68e611a4a52246c2bdf45eab7c61f3212908afd4
diff --git a/compiler/debug/elf_debug_writer.cc b/compiler/debug/elf_debug_writer.cc
index 5bfdd16..d1c10a9 100644
--- a/compiler/debug/elf_debug_writer.cc
+++ b/compiler/debug/elf_debug_writer.cc
@@ -18,6 +18,7 @@
 
 #include <vector>
 
+#include "base/array_ref.h"
 #include "debug/dwarf/dwarf_constants.h"
 #include "debug/elf_compilation_unit.h"
 #include "debug/elf_debug_frame_writer.h"
@@ -29,7 +30,6 @@
 #include "debug/method_debug_info.h"
 #include "elf_builder.h"
 #include "linker/vector_output_stream.h"
-#include "utils/array_ref.h"
 
 namespace art {
 namespace debug {