Include ui/gfx/skia_util.h instead of its .cc counterpart

SSIA.

This is a follow up of https://crrev.com/c/644946.

TBR=spang@chromium.org
BUG=786761

Change-Id: I23b278b0e32b00b8fbfccbe0cbc89a5cc9ca4833
Reviewed-on: https://chromium-review.googlesource.com/779779
Commit-Queue: Antonio Gomes <tonikitoo@igalia.com>
Reviewed-by: Antonio Gomes <tonikitoo@igalia.com>
Cr-Commit-Position: refs/heads/master@{#517881}

ui/ozone/platform/wayland/wayland_cursor.cc

@@ -9,7 +9,7 @@
 
 #include "base/memory/shared_memory.h"
 #include "third_party/skia/include/core/SkCanvas.h"
-#include "ui/gfx/skia_util.cc"
+#include "ui/gfx/skia_util.h"
 #include "ui/ozone/platform/wayland/wayland_connection.h"
 #include "ui/ozone/platform/wayland/wayland_pointer.h"