Added simple system tests for different progress indicators.

Bug: v8:6917
Change-Id: I906ddfd06e82cc19d3b2210e09457456be00309b
Cq-Include-Trybots: luci.v8.try:v8_linux64_fyi_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/852495
Commit-Queue: Michał Majewski <majeski@google.com>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50406}