win: Make chrome.7z generation more deterministic.

mini_installer.exe embeds chrome.7z, and chrome.7z contains timestamps
of all files in the archive. To make chrome.7z more deterministic, give
all files in it deterministic timestamps.

Bug: 330260
Change-Id: Ia251dd38177acbebdde288b86826986f441b2d4d
Reviewed-on: https://chromium-review.googlesource.com/c/1302393
Reviewed-by: Gabriel Charette <gab@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603171}
3 files changed