Uses the 'client.angle' and 'tryserver.angle' naming scheme that
both V8 and WebRTC use. Necessary for the scripts to work with
swarming tests.

Bug: angleproject:5114
Change-Id: I107cf0018e2173117e1d90e840b8e1419e69ef55
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2854277Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>