chromium_tests: apply chromium.get_env() when running tests

scripts/slave/recipes/chromium_trybot.expected/analyze_webkit.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]\\scripts\\slave\\kill_processes.py"
     ],
     "name": "taskkill"
   },
   {
@@ skipping 426 matching lines @@
       "Release",
       "--use-src-side-runtest-py",
       "--paths",
       "{\"checkout\": \"[SLAVE_BUILD]\\\\src\", \"runit.py\": \"RECIPE_PACKAGE_REPO[build]\\\\scripts\\\\tools\\\\runit.py\", \"runtest.py\": \"RECIPE_PACKAGE_REPO[build]\\\\scripts\\\\slave\\\\runtest.py\"}",
       "--properties",
       "{\"buildername\": \"win_chromium_rel_ng\", \"buildnumber\": 571, \"mastername\": \"tryserver.chromium.win\", \"slavename\": \"TestSlavename\", \"target_platform\": \"win\"}",
       "run",
       "--output",
       "/path/to/tmp/json"
     ],
+    "env": {
+      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "C:\\creds\\service_accounts\\service-account-goma-client.json"
+    },
     "name": "webkit_lint (with patch)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"failures\": [], @@@",
       "@@@STEP_LOG_LINE@json.output@  \"valid\": true@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]\\src\\testing\\scripts\\webkit_python_tests.py",
       "--build-config-fs",
       "Release",
       "--use-src-side-runtest-py",
       "--paths",
       "{\"checkout\": \"[SLAVE_BUILD]\\\\src\", \"runit.py\": \"RECIPE_PACKAGE_REPO[build]\\\\scripts\\\\tools\\\\runit.py\", \"runtest.py\": \"RECIPE_PACKAGE_REPO[build]\\\\scripts\\\\slave\\\\runtest.py\"}",
       "--properties",
       "{\"buildername\": \"win_chromium_rel_ng\", \"buildnumber\": 571, \"mastername\": \"tryserver.chromium.win\", \"slavename\": \"TestSlavename\", \"target_platform\": \"win\"}",
       "run",
       "--output",
       "/path/to/tmp/json"
     ],
+    "env": {
+      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "C:\\creds\\service_accounts\\service-account-goma-client.json"
+    },
     "name": "webkit_python_tests (with patch)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"failures\": [], @@@",
       "@@@STEP_LOG_LINE@json.output@  \"valid\": true@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
@@ skipping 14 matching lines @@
       "--build-number",
       "571",
       "--builder-name",
       "win_chromium_rel_ng",
       "--step-name",
       "webkit_tests (with patch)",
       "--master-name",
       "tryserver.chromium.win",
       "--debug-rwt-logging"
     ],
+    "env": {
+      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "C:\\creds\\service_accounts\\service-account-goma-client.json"
+    },
     "name": "webkit_tests (with patch)",
     "~followup_annotations": [
       "@@@STEP_TEXT@<br/>Total executed: 9001<br/>@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\chromium\\archive_layout_test_results.py",
       "--results-dir",
       "[SLAVE_BUILD]\\layout-test-results",
       "--build-dir",
       "[SLAVE_BUILD]\\src\\out",
       "--build-number",
       "571",
       "--builder-name",
       "win_chromium_rel_ng",
       "--gs-bucket",
       "gs://chromium-layout-test-archives"
     ],
+    "env": {
+      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "C:\\creds\\service_accounts\\service-account-goma-client.json"
+    },
     "name": "archive_webkit_tests_results",
     "~followup_annotations": [
       "@@@STEP_LINK@layout_test_results@https://storage.googleapis.com/chromium-layout-test-archives/win_chromium_rel_ng/571/layout-test-results/results.html@@@",
       "@@@STEP_LINK@(zip)@https://storage.googleapis.com/chromium-layout-test-archives/win_chromium_rel_ng/571/layout-test-results.zip@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]\\scripts\\slave\\process_dumps.py",
       "--target",
       "Release"
     ],
+    "env": {
+      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "C:\\creds\\service_accounts\\service-account-goma-client.json"
+    },
     "name": "process_dumps"
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]