ART: Move JNI files to runtime/jni/ .

Test: Rely on TreeHugger.
Change-Id: I9cae11191ef1567ae9453be498882a7767285140
diff --git a/runtime/reflection.cc b/runtime/reflection.cc
index 068bc28..dfa4b3d 100644
--- a/runtime/reflection.cc
+++ b/runtime/reflection.cc
@@ -23,8 +23,8 @@
 #include "common_throws.h"
 #include "dex/dex_file-inl.h"
 #include "indirect_reference_table-inl.h"
-#include "java_vm_ext.h"
-#include "jni_internal.h"
+#include "jni/java_vm_ext.h"
+#include "jni/jni_internal.h"
 #include "mirror/class-inl.h"
 #include "mirror/executable.h"
 #include "mirror/object_array-inl.h"