Isolate courgette_unittests

testing/buildbot/chromium_trybot.json

 {
   "compile_targets": [
     "all"
   ],
   "gtest_tests": [
     {
       "test": "accessibility_unittests",
       "swarming": {
         "can_use_on_swarming_builders": true
       }
@@ skipping 61 matching lines @@
       "swarming": {
         "can_use_on_swarming_builders": true
       }
     },
     {
       "test": "compositor_unittests",
       "platforms": ["linux", "win"]
     },
     {
       "test": "courgette_unittests",
+      "can_use_on_swarming_builders": true,
       "platforms": ["win"]
     },
     {
       "test": "content_browsertests",
       "swarming": {
         "can_use_on_swarming_builders": true
       }
     },
     {
       "test": "content_unittests",
@@ skipping 190 matching lines @@
   "non_filter_tests_builders": [
   ],
 
   "filter_compile_builders": [
     "win_chromium_compile_dbg",
     "win_chromium_rel_swarming",
     "win_chromium_x64_rel_swarming",
     "win8_chromium_rel"
   ]
 }