Stop to use contextmanager for goma.build_with_goma

scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json

Index: scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json
diff --git a/scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json b/scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json
index 2ecfd66f9cc6424e533282a617181854e6b5e572..31d188e0ddec7a621698370b3ff4f4e3aaef81c9 100644
--- a/scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json
+++ b/scripts/slave/recipe_modules/chromium_android/example.expected/restart_usb_builder_basic.json
@@ -311,33 +311,6 @@
     ]
   },
   {
-    "cmd": [
-      "python",
-      "-u",
-      "\nimport multiprocessing\nimport sys\n\njob_limit = 200\nif sys.platform.startswith('linux'):\n  # Use 80 for linux not to load goma backend.\n  job_limit = 80\n\ntry:\n  jobs = min(job_limit, multiprocessing.cpu_count() * 10)\nexcept NotImplementedError:\n  jobs = 50\n\nprint jobs\n"
-    ],
-    "name": "calculate the number of recommended jobs",
-    "stdout": "/path/to/tmp/",
-    "~followup_annotations": [
-      "@@@STEP_LOG_LINE@python.inline@@@@",
-      "@@@STEP_LOG_LINE@python.inline@import multiprocessing@@@",
-      "@@@STEP_LOG_LINE@python.inline@import sys@@@",
-      "@@@STEP_LOG_LINE@python.inline@@@@",
-      "@@@STEP_LOG_LINE@python.inline@job_limit = 200@@@",
-      "@@@STEP_LOG_LINE@python.inline@if sys.platform.startswith('linux'):@@@",
-      "@@@STEP_LOG_LINE@python.inline@  # Use 80 for linux not to load goma backend.@@@",
-      "@@@STEP_LOG_LINE@python.inline@  job_limit = 80@@@",
-      "@@@STEP_LOG_LINE@python.inline@@@@",
-      "@@@STEP_LOG_LINE@python.inline@try:@@@",
-      "@@@STEP_LOG_LINE@python.inline@  jobs = min(job_limit, multiprocessing.cpu_count() * 10)@@@",
-      "@@@STEP_LOG_LINE@python.inline@except NotImplementedError:@@@",
-      "@@@STEP_LOG_LINE@python.inline@  jobs = 50@@@",
-      "@@@STEP_LOG_LINE@python.inline@@@@",
-      "@@@STEP_LOG_LINE@python.inline@print jobs@@@",
-      "@@@STEP_LOG_END@python.inline@@@"
-    ]
-  },
-  {
     "cmd": [],
     "name": "preprocess_for_goma"
   },
@@ -381,13 +354,40 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
+      "\nimport multiprocessing\nimport sys\n\njob_limit = 200\nif sys.platform.startswith('linux'):\n  # Use 80 for linux not to load goma backend.\n  job_limit = 80\n\ntry:\n  jobs = min(job_limit, multiprocessing.cpu_count() * 10)\nexcept NotImplementedError:\n  jobs = 50\n\nprint jobs\n"
+    ],
+    "name": "calculate the number of recommended jobs",
+    "stdout": "/path/to/tmp/",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@python.inline@@@@",
+      "@@@STEP_LOG_LINE@python.inline@import multiprocessing@@@",
+      "@@@STEP_LOG_LINE@python.inline@import sys@@@",
+      "@@@STEP_LOG_LINE@python.inline@@@@",
+      "@@@STEP_LOG_LINE@python.inline@job_limit = 200@@@",
+      "@@@STEP_LOG_LINE@python.inline@if sys.platform.startswith('linux'):@@@",
+      "@@@STEP_LOG_LINE@python.inline@  # Use 80 for linux not to load goma backend.@@@",
+      "@@@STEP_LOG_LINE@python.inline@  job_limit = 80@@@",
+      "@@@STEP_LOG_LINE@python.inline@@@@",
+      "@@@STEP_LOG_LINE@python.inline@try:@@@",
+      "@@@STEP_LOG_LINE@python.inline@  jobs = min(job_limit, multiprocessing.cpu_count() * 10)@@@",
+      "@@@STEP_LOG_LINE@python.inline@except NotImplementedError:@@@",
+      "@@@STEP_LOG_LINE@python.inline@  jobs = 50@@@",
+      "@@@STEP_LOG_LINE@python.inline@@@@",
+      "@@@STEP_LOG_LINE@python.inline@print jobs@@@",
+      "@@@STEP_LOG_END@python.inline@@@"
+    ]
+  },
+  {
+    "cmd": [
       "RECIPE_PACKAGE_REPO[depot_tools]/ninja",
+      "-j",
+      "50",
       "-w",
       "dupbuild=err",
       "-C",
-      "[SLAVE_BUILD]/src/out/Release",
-      "-j",
-      "50"
+      "[SLAVE_BUILD]/src/out/Release"
     ],
     "env": {
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json",
@@ -458,7 +458,7 @@
       "--ninja-log-compiler",
       "goma",
       "--ninja-log-command",
-      "['RECIPE_PACKAGE_REPO[depot_tools]/ninja', '-w', 'dupbuild=err', '-C', '[SLAVE_BUILD]/src/out/Release', '-j', 50]",
+      "['RECIPE_PACKAGE_REPO[depot_tools]/ninja', '-j', 50, '-w', 'dupbuild=err', '-C', '[SLAVE_BUILD]/src/out/Release']",
       "--ninja-log-exit-status",
       "0",
       "--buildbot-buildername",