Support sharding for swarmed isolated script tests.

scripts/slave/recipes/chromium.expected/dynamic_swarmed_sharded_isolated_script_test_missing_shard.json

Index: scripts/slave/recipes/chromium.expected/dynamic_swarmed_sharded_isolated_script_test_missing_shard.json
diff --git a/scripts/slave/recipes/chromium.expected/dynamic_swarmed_passed_isolated_script_test_with_swarming_failure.json b/scripts/slave/recipes/chromium.expected/dynamic_swarmed_sharded_isolated_script_test_missing_shard.json
similarity index 93%
copy from scripts/slave/recipes/chromium.expected/dynamic_swarmed_passed_isolated_script_test_with_swarming_failure.json
copy to scripts/slave/recipes/chromium.expected/dynamic_swarmed_sharded_isolated_script_test_missing_shard.json
index ee3eec8b25cc863d729fdcd16e1e582918ee4a47..779b9632638232543cfa7e9bbbe8fb6a2197e276 100644
--- a/scripts/slave/recipes/chromium.expected/dynamic_swarmed_passed_isolated_script_test_with_swarming_failure.json
+++ b/scripts/slave/recipes/chromium.expected/dynamic_swarmed_sharded_isolated_script_test_missing_shard.json
@@ -227,7 +227,8 @@
       "@@@STEP_LOG_LINE@json.output@        \"isolate_name\": \"telemetry_gpu_unittests\", @@@",
       "@@@STEP_LOG_LINE@json.output@        \"name\": \"telemetry_gpu_unittests\", @@@",
       "@@@STEP_LOG_LINE@json.output@        \"swarming\": {@@@",
-      "@@@STEP_LOG_LINE@json.output@          \"can_use_on_swarming_builders\": true@@@",
+      "@@@STEP_LOG_LINE@json.output@          \"can_use_on_swarming_builders\": true, @@@",
+      "@@@STEP_LOG_LINE@json.output@          \"shards\": 2@@@",
       "@@@STEP_LOG_LINE@json.output@        }@@@",
       "@@@STEP_LOG_LINE@json.output@      }@@@",
       "@@@STEP_LOG_LINE@json.output@    ]@@@",
@@ -323,7 +324,7 @@
       "--priority",
       "25",
       "--shards",
-      "1",
+      "2",
       "--task-name",
       "telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571",
       "--dump-json",
@@ -380,15 +381,21 @@
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"base_task_name\": \"telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"tasks\": {@@@",
-      "@@@STEP_LOG_LINE@json.output@    \"telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571:2:0\": {@@@",
       "@@@STEP_LOG_LINE@json.output@      \"shard_index\": 0, @@@",
       "@@@STEP_LOG_LINE@json.output@      \"task_id\": \"10000\", @@@",
       "@@@STEP_LOG_LINE@json.output@      \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"@@@",
+      "@@@STEP_LOG_LINE@json.output@    }, @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571:2:1\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@      \"shard_index\": 1, @@@",
+      "@@@STEP_LOG_LINE@json.output@      \"task_id\": \"10100\", @@@",
+      "@@@STEP_LOG_LINE@json.output@      \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10100\"@@@",
       "@@@STEP_LOG_LINE@json.output@    }@@@",
       "@@@STEP_LOG_LINE@json.output@  }@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@",
-      "@@@STEP_LINK@shard #0@https://chromium-swarm.appspot.com/user/task/10000@@@"
+      "@@@STEP_LINK@shard #0@https://chromium-swarm.appspot.com/user/task/10000@@@",
+      "@@@STEP_LINK@shard #1@https://chromium-swarm.appspot.com/user/task/10100@@@"
     ]
   },
   {
@@ -402,7 +409,7 @@
       "--decorate",
       "--print-status-updates",
       "--shards",
-      "1",
+      "2",
       "telemetry_gpu_unittests/Ubuntu-12.04/eeeeeeeeee/Linux Tests/571",
       "--task-output-dir",
       "/path/to/tmp/"
@@ -412,22 +419,22 @@
     },
     "name": "telemetry_gpu_unittests on Ubuntu-12.04",
     "~followup_annotations": [
-      "step returned non-zero exit code: 255",
       "@@@STEP_LOG_LINE@outdir_json@{@@@",
-      "@@@STEP_LOG_LINE@outdir_json@  \"0/output.json\": \"{\\\"failures\\\": [], \\\"valid\\\": true}\", @@@",
-      "@@@STEP_LOG_LINE@outdir_json@  \"summary.json\": \"{\\\"shards\\\": [{\\\"internal_failure\\\": true, \\\"failure\\\": true}]}\"@@@",
+      "@@@STEP_LOG_LINE@outdir_json@  \"0/output.json\": \"{\\\"successes\\\": [\\\"test1.Test1\\\", \\\"test2.Test2\\\"], \\\"failures\\\": [], \\\"valid\\\": true}\", @@@",
+      "@@@STEP_LOG_LINE@outdir_json@  \"summary.json\": \"{\\\"shards\\\": [{\\\"internal_failure\\\": false, \\\"failure\\\": false}, {\\\"internal_failure\\\": false, \\\"failure\\\": false}]}\"@@@",
       "@@@STEP_LOG_LINE@outdir_json@}@@@",
       "@@@STEP_LOG_END@outdir_json@@@",
-      "@@@STEP_LOG_LINE@no_results_exc@Infra Failure in None@@@",
+      "@@@STEP_LOG_LINE@no_results_exc@'1/output.json'@@@",
       "@@@STEP_LOG_END@no_results_exc@@@",
       "@@@STEP_LOG_LINE@invalid_results_exc@'failures'@@@",
       "@@@STEP_LOG_END@invalid_results_exc@@@",
-      "@@@STEP_FAILURE@@@"
+      "@@@STEP_LINK@shard #0@https://chromium-swarm.appspot.com/user/task/10000@@@",
+      "@@@STEP_LINK@shard #1@https://chromium-swarm.appspot.com/user/task/10100@@@"
     ]
   },
   {
     "name": "$result",
-    "reason": "1 tests failed: ['telemetry_gpu_unittests']",
-    "status_code": 1
+    "recipe_result": null,
+    "status_code": 0

[Vadim Sh., 2016/06/17 00:31:12]

this looks wrong... it's success code. So if all swarming shards exited with 0
exit code, but didn't actually generate output.json, the recipe will interpret
it as successful step. Not sure it is red on the waterfall currently.

[Vadim Sh., 2016/06/17 00:33:28]

*not sure WHY it is red on the waterfall currently

[Ken Russell (switch to Gerrit), 2016/06/17 00:57:55]

This was happening because I synthesized the wrong return code for the step.
I've fixed that in the next patch set and the recipe fails as expected.

   }
 ]