Prep for ICU 59 update (again)

During i18n code reorg, a couple of changes for ICU 59 prep were
lost. Add them back.

See https://codereview.chromium.org/2738503008/ for the original CL.

BUG=v8:6062
TEST=v8 can be compiled with ICU 59 (hash: c28886684 ).

Change-Id: Ie19a40a9e54d0a8966dbe8e072f9afabf9e85e4f
Reviewed-on: https://chromium-review.googlesource.com/499609Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Jungshik Shin <jshin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45213}

src/intl.cc

@@ -17,14 +17,10 @@
 #include "unicode/calendar.h"
 #include "unicode/gregocal.h"
 #include "unicode/timezone.h"
-#include "unicode/uchar.h"
+#include "unicode/ustring.h"
 #include "unicode/uvernum.h"
 #include "unicode/uversion.h"
 
-#if U_ICU_VERSION_MAJOR_NUM >= 59
-#include "unicode/char16ptr.h"
-#endif
-
 namespace v8 {
 namespace internal {
 

src/runtime/runtime-intl.cc

@@ -44,9 +44,13 @@
 #include "unicode/uloc.h"
 #include "unicode/unistr.h"
 #include "unicode/unum.h"
-#include "unicode/ustring.h"
+#include "unicode/uvernum.h"
 #include "unicode/uversion.h"
 
+#if U_ICU_VERSION_MAJOR_NUM >= 59
+#include "unicode/char16ptr.h"
+#endif
+
 namespace v8 {
 namespace internal {