[android pylib] support go swarming client in gtest merge script

go swarming client have different directory structure of task outputs from python.
In go client, directory name of task output become task_id, not shard index like in python.
let me support both directory structure during migration.

This is cherry-pick of
https://chromium-review.googlesource.com/c/chromium/tools/build/+/1360817

This is to prevent infra failure like
https://ci.chromium.org/p/chromium/builders/luci.chromium.try/android-marshmallow-arm64-rel/145571

Bug: 894045
Change-Id: I91da3b0b99ea7a984852ee76f20a09f23e9f490e
Reviewed-on: https://chromium-review.googlesource.com/c/1364995
Reviewed-by: Marc-Antoine Ruel <maruel@chromium.org>
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Cr-Commit-Position: refs/heads/master@{#614380}
1 file changed