Convert test_support source sets to static libs

components/autofill/core/browser/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/chrome_build.gni")
 
 # GYP version: components/autofill.gyp:autofill_core_browser
 source_set("browser") {
   sources = [
     "address.cc",
@@ skipping 193 matching lines @@
     "//components/autofill/core/browser/proto",
   ]
 
   configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
   if (is_mac) {
     libs = [ "AddressBook.framework" ]
   }
 }
 
-source_set("test_support") {
+static_library("test_support") {
   testonly = true
   sources = [
     "autofill_test_utils.cc",
     "autofill_test_utils.h",
     "data_driven_test.cc",
     "data_driven_test.h",
     "suggestion_test_helpers.h",
     "test_autofill_client.cc",
     "test_autofill_client.h",
     "test_autofill_driver.cc",
@@ skipping 126 matching lines @@
     "//sync",
     "//sync:test_support_sync_api",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/libaddressinput:util",
     "//third_party/libphonenumber",
     "//ui/base",
     "//url",
   ]
 }