[fuchsia] Add host chromedriver build and CIPD package.

* Add the host chromedriver binary as part of the Fuchsia build.
* Add a CIPD package to upload a stripped chromedriver binary.

Bug: IN-1321 (Fuchsia internal)
Change-Id: Ia414914304ede7a54ff097365bb72cba6674e5ae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1719377
Commit-Queue: Fabrice de Gans-Riberi <fdegans@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Auto-Submit: Fabrice de Gans-Riberi <fdegans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#682114}

• BUILD.gn[diff]
• fuchsia/cipd/BUILD.gn[diff]