Add .sha1 file for the first ever translation screenshot

This is the first translation screenshot to be used by
http://go/chrome-translation-screenshots. This CL adds the SHA1
hash of the actual image which is stored in the Google Cloud
Storage bucket at gs://chromium-translation-screenshots

The screenshot can be downloaded using the gsutil tool like so:
gsutil cp gs://chromium-translation-screenshots/378650e81625e476126a1a3d4b6ff559df54ef7c ~/translation.png

Bug: 814897
Change-Id: I95bff8b6ac41be48a13212ad2bc9b4dcd5c4518b
Reviewed-on: https://chromium-review.googlesource.com/976950Reviewed-by: Emily Stark <estark@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Mustafa Emre Acer <meacer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547763}

components/security_interstitials_strings_grdp/IDS_CAPTIVE_PORTAL_HEADING_WIRED.png.sha1

+378650e81625e476126a1a3d4b6ff559df54ef7c
\ No newline at end of file

components/security_interstitials_strings_grdp/OWNERS

+file://components/security_interstitials/OWNERS