ART: Move JNI files to runtime/jni/ .

Test: Rely on TreeHugger.
Change-Id: I9cae11191ef1567ae9453be498882a7767285140
diff --git a/runtime/native/java_lang_reflect_Executable.cc b/runtime/native/java_lang_reflect_Executable.cc
index b129c66..9a2d302 100644
--- a/runtime/native/java_lang_reflect_Executable.cc
+++ b/runtime/native/java_lang_reflect_Executable.cc
@@ -22,7 +22,7 @@
 #include "art_method-inl.h"
 #include "dex/dex_file_annotations.h"
 #include "handle.h"
-#include "jni_internal.h"
+#include "jni/jni_internal.h"
 #include "mirror/class-inl.h"
 #include "mirror/method.h"
 #include "mirror/object-inl.h"