Remove the unmaintained performance monitor.

chrome/browser/ui/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 
 gypi_values = exec_script(
     "//build/gypi_to_gn.py",
@@ skipping 65 matching lines @@
   forward_dependent_configs_from = [
     "//components/dom_distiller/core",
     "//sync",
   ]
 
   if (!is_ios) {
     sources += rebase_path(gypi_values.chrome_browser_ui_non_ios_sources,
                            ".", "//chrome")
     deps += [
       "//chrome/browser/devtools",
-      "//chrome/browser/performance_monitor",
       "//chrome/browser/ui/webui/omnibox:mojo_bindings",
       "//chrome/common/extensions/api",
       "//chrome/common/extensions/api:api_registration",
       "//chrome/installer/util",
       "//components/autofill/content/browser:risk_proto",
       "//components/power",
       "//device/bluetooth",
       "//device/nfc",
       "//media",
       "//mojo/system",
@@ skipping 318 matching lines @@
     script = "//chrome/tools/build/mac/generate_localizer"
     sources = [ ]
     table_path = "$target_gen_dir/ui_localizer_table.h"
     outputs = [ table_path ]
     args = [ rebase_path(table_path, root_build_dir) ] +
              rebase_path(nib_gypi_values.mac_translated_xibs,
                          root_build_dir,
                          "//chrome")
   }
 }