Adding Athenas browser and unit tests which are required for running the tests on a buildbot

testing/buildbot/chromium_trybot.json

 {
   "compile_targets": [
     "all"
   ],
   "gtest_tests": [
     "accessibility_unittests",
     "app_list_unittests",
     {
       "test": "ash_unittests",
       "chromium_configs": ["chromium_chromeos", "chromium_chromeos_clang"],
@@ skipping 187 matching lines @@
       "platforms": ["mac"]
     },
     {
       "test": "chromeos_unittests",
       "platforms": ["linux"],
       "chromium_configs": ["chromium_chromeos", "chromium_chromeos_clang"]
     },
     {
       "test": "athena_unittests",
       "platforms": ["linux"],
-      "chromium_configs": ["chromium_chromeos", "chromium_chromeos_clang"]
+      "chromium_configs": ["chromium_chromeos_athena"]

[oshima, 2014/10/16 09:43:22]

please do not remove athena_unittests from chromeos bots. They still need to run
athena_unittests.

[Mr4D (OOO till 08-26), 2014/10/16 14:52:55]

We get our own builder and unit tester. In fact - the missing CL will land
today.

[oshima, 2014/10/16 15:52:22]

We still need this for two reasons.
1) main waterfall runs this test.
2) athena_main and athena_unittests should build and pass without use_athena=1.

     },
     {
       "test": "display_unittests",
       "platforms": ["linux"]
     },
     {
       "test": "ozone_unittests",
       "platforms": ["linux"],
       "chromium_configs": ["chromium_chromeos_ozone"]
     }
   ],
 
   "non_filter_builders": [
   ],
 
   "non_filter_tests_builders": [
   ],
 
   "filter_compile_builders": [
     "win_chromium_compile_dbg",
     "win_chromium_rel_swarming",
     "win_chromium_x64_rel_swarming",
     "win8_chromium_rel"
   ]
 }