ART: Move JNI files to runtime/jni/ .

Test: Rely on TreeHugger.
Change-Id: I9cae11191ef1567ae9453be498882a7767285140
diff --git a/runtime/native/java_lang_String.cc b/runtime/native/java_lang_String.cc
index b5aea7c..8976058 100644
--- a/runtime/native/java_lang_String.cc
+++ b/runtime/native/java_lang_String.cc
@@ -19,7 +19,7 @@
 #include "nativehelper/jni_macros.h"
 
 #include "common_throws.h"
-#include "jni_internal.h"
+#include "jni/jni_internal.h"
 #include "mirror/array.h"
 #include "mirror/object-inl.h"
 #include "mirror/string-inl.h"