Revert "Lacros: create lacros tast test targets"

This reverts commit e2f3b551.

Reason for revert:

Breaks local user flow when entering chrome_sdk

ERROR at //build/config/chromeos/rules.gni:180:11: Undefined identifier.
          _symlink_targets[2],
          ^-----------------
See //chromeos/BUILD.gn:239:3: whence it was called.
  generate_runner_script("cros_test_wrapper") {
  ^--------------------------------------------
See //BUILD.gn:442:7: which caused the file to be included.
      "//chromeos:chromeos_unittests",

Original change's description:
> Lacros: create lacros tast test targets
>
> This CL creates gn targets for lacros tast tests, and the main
> motivation is to run lacros tast tests on Chromium CI.
>
> Bug: 1158590
> Change-Id: I783779c3386a39743b8227367189b0b87832b9dc
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2606188
> Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
> Reviewed-by: Ben Pastene <bpastene@chromium.org>
> Reviewed-by: Dirk Pranke <dpranke@google.com>
> Cr-Commit-Position: refs/heads/master@{#844127}

TBR=dpranke@google.com,liaoyuke@chromium.org,bpastene@chromium.org,chromium-scoped@luci-project-accounts.iam.gserviceaccount.com

Change-Id: I1e51bf2e6aa97bfc40beba7d2693b68361cab2bc
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1158590
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2633782Reviewed-by: Yuke Liao <liaoyuke@chromium.org>
Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#844180}

chromeos/lacros/BUILD.gn

@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chromeos/rules.gni")
 import("//build/config/chromeos/ui_mode.gni")
 import("//build/config/linux/gtk/gtk.gni")
 import("//build/lacros/lacros_resource_sizes.gni")
@@ -31,41 +30,3 @@ component("lacros") {
 lacros_resource_sizes_test("resource_sizes_lacros_chrome") {
   data_deps = [ "//chrome:chrome" ]
 }
-
-# "cros_board" set in the GN args defines the board used to build lacros-chrome,
-# while the "override_board" here defines the board on which to test the built
-# binary, for more details, please refer to the "generate_runner_script"
-# template in //build/config/chromeos/rules.gni.
-template("lacros_tast_test_helper") {
-  forward_variables_from(invoker, [ "override_board" ])
-  assert(defined(override_board), "override_board is required")
-  lacros_tast_test(target_name) {
-    # TODO(crbug.com/1158590): use --attr-expr instead of hard-coding the tests.
-    tast_tests = [
-      "lacros.AudioPlay",
-      "lacros.AppLauncherLaunch",
-      "lacros.Basic",
-      "lacros.ShelfLaunch",
-    ]
-  }
-}
-
-# On Chromium CI, only a very limited number of boards are supported:
-# amd64-generic, eve, kevin etc, so just hard-coding them for simplicity.
-if (is_chromeos_device) {
-  _boards = string_split(cros_boards, ":") +
-            string_split(cros_boards_with_qemu_images, ":")
-  foreach(b, _boards) {
-    if (b == "amd64-generic") {
-      lacros_tast_test_helper("lacros_tast_tests_amd64_generic") {
-        override_board = "amd64-generic"
-      }
-    }
-
-    if (b == "eve") {
-      lacros_tast_test_helper("lacros_tast_tests_eve") {
-        override_board = "eve"
-      }
-    }
-  }
-}