Convert some component source sets to static library

components/wifi/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.
 
 component("wifi") {
   sources = [
     "network_properties.cc",
     "network_properties.h",
     "wifi_export.h",
     "wifi_service.cc",
@@ skipping 17 matching lines @@
 
   if (is_mac) {
     libs = [
       "CoreWLAN.framework",
       "Foundation.framework",
       "SystemConfiguration.framework",
     ]
   }
 }
 
-source_set("test_support") {
+static_library("test_support") {
   sources = [
     "fake_wifi_service.cc",
     "fake_wifi_service.h",
   ]
 
   deps = [
     ":wifi",
     "//base",
     "//components/onc",
   ]
 }
 
 executable("wifi_test") {
   sources = [
     "wifi_test.cc",
   ]
 
   deps = [
     ":wifi",
     "//base",
     "//build/config/sanitizers:deps",
     "//build/win:default_exe_manifest",
     "//components/onc",
   ]
 }