Add a tool to upload translation screenshots to content addressed Cloud Storage

This tool scans for any screenshots (png only) associated with grd files and uploads them to Google Cloud Storage using upload_to_google_storage.py.

upload_to_google_storage.py is a tool that maintains content addressed files. It stores files with their sha1 hashes as filenames.

The storage bucket name used in the tool is tentative.

For details, see the design doc at http://go/chrome-translation-screenshots#heading=h.cyt0azox2105

Change-Id: Ide06aa679489a65887df9c58948c8adde12d3eba
Bug: 814901
Reviewed-on: https://chromium-review.googlesource.com/922686
Commit-Queue: Mustafa Emre Acer <[email protected]>
Reviewed-by: anthonyvd <[email protected]>
Reviewed-by: Aaron Gable <[email protected]>
Reviewed-by: Dirk Pranke <[email protected]>
Cr-Commit-Position: refs/heads/master@{#541898}
15 files changed