Interpret collected iOS Swarming task results

scripts/slave/recipe_modules/ios/example.expected/errors.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--master",
       "chromium.fake",
       "--builder",
       "ios",
@@ skipping 585 matching lines @@
     ]
   },
   {
     "cmd": [],
     "name": "trigger.[trigger] fake test 3 (fake device iOS 8.1)",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_TEXT@Requested unsupported device type.@@@",
       "@@@STEP_LOG_LINE@supported devices@iPad Air@@@",
       "@@@STEP_LOG_LINE@supported devices@iPhone 5s@@@",
+      "@@@STEP_LOG_LINE@supported devices@iPhone 6s@@@",
       "@@@STEP_LOG_END@supported devices@@@",
       "@@@STEP_EXCEPTION@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]/swarming.client/swarming.py",
       "trigger",
@@ skipping 152 matching lines @@
       "@@@STEP_EXCEPTION@@@"
     ]
   },
   {
     "name": "$result",
     "reason": "Failed fake test 1 (fake device iOS 8.1), fake test 3 (fake device iOS 8.1), fake test 4 (iPhone 5s iOS 8.1).",
     "recipe_result": null,
     "status_code": 1
   }
 ]