Add minimal test-media folder for webxr-samples

This folder is intended to contain a minimal set of small files needed to run
automated tests. Currently this is just the cube-sea texture. For larger files,
the intent is to use a local media folder for ad-hoc testing, or in the future
use cloud storage via DEPS indirection.

To save space, the image file is recompressed from the original PNG to WEBP
using https://squoosh.app/ . (WebP format, effort 6, quality 75.)

Bug: 923149
Change-Id: I18a89ab103a5670b49489bfe102e4a20a59a4138
Reviewed-on: https://chromium-review.googlesource.com/c/1448336
Reviewed-by: Brian Sheedy <bsheedy@chromium.org>
Commit-Queue: Klaus Weidner <klausw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#628383}
3 files changed