Re-land "Flip 'Linux x64' bot on chromium waterfall to GN."

tools/mb/mb_config.pyl

Index: tools/mb/mb_config.pyl
diff --git a/tools/mb/mb_config.pyl b/tools/mb/mb_config.pyl
index 14d6ae9769185e45f08d8012fa25227a7c938fa1..dd1c69d1e44af966c82f00a615269d5498091c30 100644
--- a/tools/mb/mb_config.pyl
+++ b/tools/mb/mb_config.pyl
@@ -59,10 +59,10 @@
     # This is just for completeness; any bot that uses this config should never actually run MB.
     'none': ['none'],
 
+    'noswarming_gn_release_bot': ['noswarming', 'gn', 'release_bot'],
     'noswarming_gyp_release_bot': ['noswarming', 'gyp', 'release_bot'],
-    'noswarming_gyp_release_bot_linux_dump_symbols': ['noswarming', 'gyp', 'release_bot', 'linux_dump_symbols'],
     'noswarming_gyp_release_bot_mac_strip': ['noswarming', 'gyp', 'release_bot', 'mac_strip'],
-    'noswarming_gyp_release_bot_x86_linux_dump_symbols': ['noswarming', 'gyp', 'release_bot', 'x86', 'linux_dump_symbols'],
+    'noswarming_gyp_release_bot_x86': ['noswarming', 'gyp', 'release_bot', 'x86'],
 
     'swarming_asan_lsan_gyp_release_trybot': ['swarming', 'asan', 'lsan', 'release_trybot'],
     'swarming_msan_gyp_release_trybot': ['swarming', 'chromeos', 'msan', 'gyp', 'release_trybot'],
@@ -237,11 +237,6 @@
 
     'libfuzzer': { 'gn_args': 'use_libfuzzer=true' },
 
-    'linux_dump_symbols': {
-      'gn_args': '', # TODO(GYP): Port linux_dump_symbols?
-      'gyp_defines': 'linux_dump_symbols=1',
-    },
-
     'lsan': {
       'gn_args': 'use_lsan=true',
       'gyp_defines': 'lsan=1',
@@ -277,6 +272,7 @@
     },
 
     'noswarming': {
+      # test_isolation_mode doesn't exist in a GN build (it's always a no-op).
       'gn_args': '',
       'gyp_defines': 'test_isolation_mode=noop',
     },
@@ -360,8 +356,8 @@
     'chromium': {
       'Win': 'noswarming_gyp_release_bot',
       'Mac': 'noswarming_gyp_release_bot_mac_strip',
-      'Linux x64': 'noswarming_gyp_release_bot_linux_dump_symbols',
-      'Linux': 'noswarming_gyp_release_bot_x86_linux_dump_symbols',
+      'Linux x64': 'noswarming_gn_release_bot',
+      'Linux': 'noswarming_gyp_release_bot_x86',
       'Android': 'android_gyp_release_bot_minimal_symbols',
     },
     'chromium.android': {
@@ -503,7 +499,7 @@
       'linux_arm_compile': 'swarming_gyp_release_trybot_arm',
       'linux_chromium_compile_dbg_32_ng': 'swarming_gyp_debug_trybot_x86',
       'linux_chromium_dbg_32_ng': 'swarming_gyp_debug_trybot_x86',
-      'linux_chromium_archive_rel_ng': 'noswarming_gyp_release_bot_linux_dump_symbols',
+      'linux_chromium_archive_rel_ng': 'noswarming_gn_release_bot',
       'linux_chromium_clobber_rel_ng': 'gyp_release_trybot',
       'linux_chromium_gn_upload': 'gn_linux_upload',
       'cast_shell_linux': 'cast_gyp_release_trybot',