infra: Migrate linux_chromium_tsan_rel_ng to builderfull.

Machines are allocated in crrev.com/i/3459783

This'll be the last builder in the 8-core xenial builderless to be
migrated. chromium_presubmit will remain since it's not as affected by
cache age, and it will also provide signal to how the pool is doing
since it'll be the only alertable builder that remains.

Bug: 1140727
Change-Id: I5b78d52e67e48f4dc0dc6c7edc20b6f2faa559b9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2585385Reviewed-by: Haiyang Pan <hypan@google.com>
Reviewed-by: Garrett Beaty <gbeaty@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835783}

infra/config/generated/cr-buildbucket.cfg

@@ -36158,12 +36158,11 @@ buckets {
       name: "linux_chromium_tsan_rel_ng"
       swarming_host: "chromium-swarm.appspot.com"
       swarming_tags: "vpython:native-python-wrapper"
-      dimensions: "builderless:1"
+      dimensions: "builder:linux_chromium_tsan_rel_ng"
       dimensions: "cores:8"
       dimensions: "cpu:x86-64"
       dimensions: "os:Ubuntu-16.04"
       dimensions: "pool:luci.chromium.try"
-      dimensions: "ssd:0"
       exe {
         cipd_package: "infra/recipe_bundles/chromium.googlesource.com/chromium/tools/build"
         cipd_version: "refs/heads/master"

infra/config/subprojects/chromium/try.star

@@ -1168,6 +1168,7 @@ try_.chromium_linux_builder(
 try_.chromium_linux_builder(
     name = "linux_chromium_tsan_rel_ng",
     branch_selector = branches.STANDARD_MILESTONE,
+    builderless = not settings.is_master,
     goma_jobs = goma.jobs.J150,
     main_list_view = "try",
     tryjob = try_.job(),