Remove shared_utils.h, use angle_common instead. This saves us from needing to replicate the same code in two places. BUG=angleproject:956 Change-Id: Ibc80997eec184d0d5aa9c6c076c9d4507fbf8caa Reviewed-on: https://chromium-review.googlesource.com/262776 Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Brandon Jones <bajones@chromium.org> Tested-by: Jamie Madill <jmadill@chromium.org>