Revert of Download the hermetic xcode toolchain on all bots that target mac.

scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json

Index: scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json
diff --git a/scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json b/scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json
index 2323cb6db2ca63a9cd0d18f9d4f1e191160987ba..e8578f68e3b5b8ac9b67d391c7da22abfa070b33 100644
--- a/scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json
+++ b/scripts/slave/recipes/chromium.expected/full_chromium_webkit_WebKit_Mac10_11__retina_.json
@@ -200,7 +200,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout/src",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json",
       "GYP_CHROMIUM_NO_ACTION": "1",
       "GYP_DEFINES": "clang=1 component=static_library gomadir='[CACHE]/cipd/goma' target_arch=x64 test_isolation_mode=prepare use_goma=1",
@@ -297,7 +296,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout/src",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "generate_build_files",
@@ -318,7 +316,6 @@
       "/path/to/tmp/json"
     ],
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "clang_revision",
@@ -371,7 +368,6 @@
       "browser_tests_run"
     ],
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "compile",
@@ -425,7 +421,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "find isolated tests",
@@ -447,7 +442,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "[error] browser_tests",
@@ -495,7 +489,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "webkit_tests",
@@ -525,7 +518,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "archive_webkit_tests_results",
@@ -543,7 +535,6 @@
     ],
     "cwd": "[BUILDER_CACHE]/mac_layout",
     "env": {
-      "FORCE_MAC_TOOLCHAIN": "1",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "[collect error] browser_tests",