Swarm setup_unittests on FYI bots.

testing/buildbot/chromium.win.json

 {
   "Vista Tests (1)": {
     "gtest_tests": [
       {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "accessibility_unittests"
       },
       {
@@ skipping 220 matching lines @@
         },
         "test": "sbox_unittests"
       },
       {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "sbox_validation_tests"
       },
       {
+        "test": "setup_unittests"

[M-A Ruel, 2015/07/13 20:26:00]

Please have it run on swarming, otherwise you'll become a blocker for
http://crbug.com/496321.

[grt (UTC plus 2), 2015/07/13 20:54:17]

This can't be as simple as "can_use_on_swarming_builders": true, can it? What do
I need to do to see if it actually works on swarming? .isolate-or-something? i
can haz pointer to instructions?

[M-A Ruel, 2015/07/13 22:29:57]

https://codereview.chromium.org/1220833004 is a good example.

+      },
+      {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "skia_unittests"
       },
       {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "sql_unittests"
@@ skipping 1623 matching lines @@
         "name": "telemetry_perf_unittests",
         "script": "telemetry_perf_unittests.py"
       },
       {
         "name": "nacl_integration",
         "script": "nacl_integration.py"
       }
     ]
   }
 }