Converted accessibility_unittests to run on Swarming everywhere.

testing/buildbot/chromium.chromiumos.json

Index: testing/buildbot/chromium.chromiumos.json
diff --git a/testing/buildbot/chromium.chromiumos.json b/testing/buildbot/chromium.chromiumos.json
index 8e1edf546d64fbebd03f7190724ea711f932de59..a802b831942521c8497327735c5915c8c5d88967 100644
--- a/testing/buildbot/chromium.chromiumos.json
+++ b/testing/buildbot/chromium.chromiumos.json
@@ -2,6 +2,9 @@
   "Linux ChromiumOS Ozone Tests (1)": {
     "gtest_tests": [
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "accessibility_unittests"
       },
       {
@@ -164,6 +167,9 @@
   "Linux ChromiumOS Tests (1)": {
     "gtest_tests": [
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "accessibility_unittests"
       },
       {
@@ -340,6 +346,9 @@
   "Linux ChromiumOS Tests (dbg)(1)": {
     "gtest_tests": [
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "accessibility_unittests"
       },
       {