headless: Don't run tests during the build

testing/buildbot/chromium.fyi.json

 {
   "Android Asan Builder Tests (dbg)": {
     "gtest_tests": [
       {
         "args": [
           "--tool=asan"
         ],
         "swarming": {
           "can_use_on_swarming_builders": false
         },
@@ skipping 9693 matching lines @@
           "can_use_on_swarming_builders": false
         },
         "test": "headless_browsertests"
       },
       {
         "swarming": {
           "can_use_on_swarming_builders": false
         },
         "test": "headless_unittests"
       }
+    ],
+    "scripts": [
+      {
+        "name": "client_api_generator_unittest",
+        "script": "headless/lib/browser/client_api_generator_unittest.py"

[perezju, 2016/10/11 10:25:01]

It looks like other scripts are given relative to src/testing/scripts/, and many
are just wrappers around the actual test scripts, see:

https://chromium.googlesource.com/chromium/src/+/master/testing/scripts

+phajdan who should know more about these.

[Paweł Hajdan Jr., 2016/10/11 18:10:01]

Yup. Not only they need to be there, but also there's specific protocol for
this. See existing examples and let me know if you have any questions.

My general design suggestion would be to write generic python unit test script,
which takes specific file or directory as argument.

Dirk may have further suggestions, e.g. related to his typ test harness.

[Dirk Pranke, 2016/10/11 18:23:28]

You should look at the scripts in //testing/scripts (like telemetry_unittests.py
or webkit_unittests.py), and, yes, using //third_party/typ will probably
simplify this. 

We don't currently have a single wrapper script. It's possible that we could
write one; I'm not sure if the script would end up growing too many arguments to
be worth it, though.

+      }
     ]
   },
   "LTO Linux": {
     "gtest_tests": [
       {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "accessibility_unittests"
       },
@@ skipping 2757 matching lines @@
       },
       {
         "swarming": {
           "can_use_on_swarming_builders": true
         },
         "test": "views_unittests"
       }
     ]
   }
 }