Add test config for the builder linux-inverse-fieldtrials-fyi-rel

Bug: 1099916
Change-Id: I76e4473a95e9273283fa39cdd62a9c51404444c7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2414830
Auto-Submit: Haiyang Pan <hypan@google.com>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#807614}

testing/buildbot/waterfalls.pyl

@@ -2394,6 +2394,14 @@
           'gtest_tests': 'fieldtrial_browser_tests',
         },
       },
+      'linux-inverse-fieldtrials-fyi-rel': {
+        'mixins': [
+          'linux-xenial',
+        ],
+        'test_suites': {
+          'gtest_tests': 'chromium_linux_gtests',
+        },
+      },
       'linux-lacros-tester-fyi-rel': {
         'additional_compile_targets': [
           'chrome',