GitLab

This CL:
- Renames the resources in webapk/libs/common/res_splash to avoid
the need for merging resources with the same name prior to uploading
them to the Google storage build bucket.
- Adds a PRESUBMIT check to ensure that resource files names in
webapk/shell_apk/res differ from the resource file names in
webapk/libs/common/res_splash

BUG=969591

Change-Id: I8aa6062e8f9b37d008d185ea45dc4f04606d2c03
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1642976
Commit-Queue: Peter Kotwicz <pkotwicz@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666066}