V8: Use default compiler where possible

scripts/slave/recipes/v8.expected/full_client_v8_V8_Linux___full_debug.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--master",
       "client.v8",
       "--builder",
       "V8 Linux - full debug",
@@ skipping 102 matching lines @@
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[depot_tools]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]/v8",
     "env": {
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json",
-      "GYP_DEFINES": "clang=1 gomadir='[CACHE]/cipd/goma' target_arch=ia32 use_goma=1 v8_enable_slow_dchecks=1 v8_optimized_debug=0 v8_target_arch=ia32",
+      "GYP_DEFINES": "gomadir='[CACHE]/cipd/goma' target_arch=ia32 use_goma=1 v8_enable_slow_dchecks=1 v8_optimized_debug=0 v8_target_arch=ia32",
       "GYP_GENERATORS": "ninja",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
     },
     "name": "gclient runhooks"
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]/scripts/tools/runit.py",
@@ skipping 55 matching lines @@
     ],
     "name": "rmtree [TMP_BASE]/v8_gn_tmp_1",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import shutil, sys@@@",
       "@@@STEP_LOG_LINE@python.inline@shutil.rmtree(sys.argv[1])@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
-    "allow_subannotations": true,
-    "cmd": [
-      "python",
-      "-u",
-      "RECIPE_PACKAGE_REPO[build]/scripts/slave/clang_revision.py",
-      "--src-dir",
-      "[SLAVE_BUILD]/v8",
-      "--output-json",
-      "/path/to/tmp/json"
-    ],
-    "env": {
-      "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
-    },
-    "name": "clang_revision",
-    "~followup_annotations": [
-      "@@@STEP_LOG_LINE@json.output@{@@@",
-      "@@@STEP_LOG_LINE@json.output@  \"clang_revision\": \"123456-7\"@@@",
-      "@@@STEP_LOG_LINE@json.output@}@@@",
-      "@@@STEP_LOG_END@json.output@@@"
-    ]
-  },
-  {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]/scripts/tools/runit.py",
       "--show-path",
       "python",
       "RECIPE_PACKAGE_REPO[build]/scripts/slave/compile.py",
       "--gsutil-py-path",
       "RECIPE_PACKAGE_REPO[depot_tools]/gsutil.py",
       "--ninja-path",
       "RECIPE_PACKAGE_REPO[depot_tools]/ninja",
       "--target",
       "Debug",
       "--src-dir",
       "[SLAVE_BUILD]/v8",
       "--goma-cache-dir",
       "[GOMA_CACHE]",
       "--build-tool",
       "ninja",
       "--compiler",
-      "goma-clang",
+      "goma",
       "--goma-jsonstatus",
       "/path/to/tmp/json",
       "--goma-service-account-json-file",
       "/creds/service_accounts/service-account-goma-client.json",
       "--goma-dir",
       "[CACHE]/cipd/goma",
       "--"
     ],
     "env": {
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
@@ skipping 43 matching lines @@
       "@@@STEP_LOG_LINE@durations@Duration: 00:00:101@@@",
       "@@@STEP_LOG_END@durations@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]