This has been failing since at least https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/fuchsia-fyi-x64-rel/3877 on September 26th. :(

This was regressed by https://chromium-review.googlesource.com/1168479, which gave TestLauncher batch processes isolated /data directories.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/90f3c584cc0260de1da8d35d3844782724dc75e6

commit 90f3c584cc0260de1da8d35d3844782724dc75e6
Author: Kevin Marshall <kmarshall@chromium.org>
Date: Fri Oct 05 18:01:13 2018

[fuchsia] Fix net tests by deploying configs to new "/test-shared" dir.

Net tests broke because test process' /data directories are now isolated
and can't be used for sharing data out-of-process. The net test launcher
depends on the old behavior for deploying configuration files to test
code.

This CL designates a special path "/data/shared" into which shared
files will be placed. The shared directory will be mounted at
"/test-shared" in the test process' namespace.

The net test launcher & test code are modified to use the new paths.

TBR=mmenke@chromium.org

Bug:  891732 
Change-Id: Id94bffe05a3b140ed60e42507cdc8d238677f202
Reviewed-on: https://chromium-review.googlesource.com/c/1259829
Commit-Queue: Kevin Marshall <kmarshall@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#597193}
[modify] https://crrev.com/90f3c584cc0260de1da8d35d3844782724dc75e6/base/test/launcher/test_launcher.cc
[modify] https://crrev.com/90f3c584cc0260de1da8d35d3844782724dc75e6/build/fuchsia/net_test_server.py
[modify] https://crrev.com/90f3c584cc0260de1da8d35d3844782724dc75e6/net/test/spawned_test_server/remote_test_server_config.cc