Tracking mock_process_thread with a GN target

webrtc/modules/utility/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("../../webrtc.gni")
 
@@ skipping 22 matching lines @@
     "..:module_api",
     "../..:webrtc_common",
     "../../audio/utility:audio_frame_operations",
     "../../common_audio",
     "../../rtc_base:rtc_task_queue",
     "../../system_wrappers",
     "../media_file",
   ]
 }
 
+rtc_source_set("mock_process_thread") {
+  testonly = true
+  sources = [
+    "include/mock/mock_process_thread.h",
+  ]
+  deps = [
+    ":utility",
+    "../../rtc_base:rtc_base_approved",
+    "../../test:test_support",
+  ]
+}
+
 if (rtc_include_tests) {
   rtc_source_set("utility_unittests") {
     testonly = true
 
     # Skip restricting visibility on mobile platforms since the tests on those
     # gets additional generated targets which would require many lines here to
     # cover (which would be confusing to read and hard to maintain).
     if (!is_android && !is_ios) {
       visibility = [ "..:modules_unittests" ]
     }
     sources = [
       "source/process_thread_impl_unittest.cc",
     ]
     deps = [
       ":utility",
       "..:module_api",
       "../../rtc_base:rtc_task_queue",
       "../../test:test_support",
       "//testing/gmock",
     ]
   }
 }