Adding perf test isolate and gn build target for swarming the benchmarks.

tools/mb/mb_config.pyl

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   # This is a map of buildbot master names -> buildbot builder names ->
   # config names (where each config name is a key in the 'configs' dict,
   # below). MB uses this dict to look up which config to use for a given bot.
   'masters': {
     'chromeos.chrome': {
@@ skipping 491 matching lines @@
       'Windows Content Browser (DrMemory)': 'none',
       'Windows Unit (DrMemory full) (1)': 'none',
       'Windows Unit (DrMemory full) (2)': 'none',
       'Windows Unit (DrMemory full) (3)': 'none',
       'Windows Unit (DrMemory full) (4)': 'none',
       'Windows Unit (DrMemory full) (5)': 'none',
       'Windows Unit (DrMemory x64)': 'none',
       'Windows Unit (DrMemory)': 'none',
     },
 
+    'chromium.perf.fyi': {
+      'Win 10 Low-End 2 Core Perf': 'none',
+      'Win 10 Low-End 4 Core Perf': 'none',
+    },
+
     'chromium.perf': {
       'Android Builder': 'gn_official_goma_minimal_symbols_android',
       'Android Galaxy S5 Perf (1)': 'none',
       'Android Galaxy S5 Perf (2)': 'none',
       'Android Galaxy S5 Perf (3)': 'none',
       'Android Nexus5 Perf (1)': 'none',
       'Android Nexus5 Perf (2)': 'none',
       'Android Nexus5 Perf (3)': 'none',
       'Android Nexus5X Perf (1)': 'none',
       'Android Nexus5X Perf (2)': 'none',
@@ skipping 1946 matching lines @@
     },
 
     'drfuzz': { 'gn_args': 'use_drfuzz=true' },
 
     'drmemory': {
       'gn_args': 'is_component_build=true enable_iterator_debugging=false',
       'gyp_defines': 'component=shared_library build_for_tool=drmemory',
     },
   },
 }