[test] Migrate last test configs

Also use low experiment percentage on CQ, since the builder's output is unused.

NOTRY=true
TBR=sergiyb@chromium.org

Bug: chromium:830557
Change-Id: Id024ab16e2944ec5e94b0209672ed6b77ae322a8
Reviewed-on: https://chromium-review.googlesource.com/c/1296466Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56947}

infra/config/cq.cfg

@@ -42,9 +42,11 @@ verifiers {
         name: "v8_linux64_rel_ng_triggered"
         triggered_by: "v8_linux64_rel_ng"
       }
+      # TODO(machenbach): Figure out if bot should be removed or if
+      # functionality should be revived.
       builders {
         name: "v8_linux64_sanitizer_coverage_rel"
-        experiment_percentage: 100
+        experiment_percentage: 10
       }
       builders { name: "v8_linux64_verify_csa_rel_ng" }
       builders {

infra/testing/builders.pyl

@@ -299,6 +299,11 @@
       {'name': 'v8testing', 'shards': 2},
     ],
   },
+  'v8_linux64_sanitizer_coverage_rel': {
+    'tests': [
+      {'name': 'v8testing', 'shards': 3},
+    ],
+  },
   'v8_linux64_tsan_rel': {
     'tests': [
       {'name': 'benchmarks'},