Removing WEBRTC_BUILD_LIBEVENT macro definition

webrtc/rtc_base/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("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 271 matching lines @@
       } else {
         data += [ "$clang_base_path/lib/clang/$clang_version/lib/windows/clang_rt.asan_dynamic-i386.dll" ]
       }
     }
   }
   if (is_nacl) {
     deps += [ "//native_client_sdk/src/libraries/nacl_io" ]
   }
 }
 
-config("enable_libevent_config") {
-  defines = [ "WEBRTC_BUILD_LIBEVENT" ]
-}
-
 rtc_source_set("rtc_task_queue") {
   deps = [
     ":rtc_base_approved",
   ]
   public_deps = [
     ":rtc_task_queue_api",
   ]
 
   if (rtc_link_task_queue_impl) {
     deps += [ ":rtc_task_queue_impl" ]
@@ skipping 33 matching lines @@
   } else {
     if (rtc_build_libevent) {
       deps += [ "//base/third_party/libevent" ]
     }
     if (rtc_enable_libevent) {
       sources = [
         "task_queue_libevent.cc",
         "task_queue_posix.cc",
         "task_queue_posix.h",
       ]
-      all_dependent_configs = [ ":enable_libevent_config" ]
     } else {
       if (is_mac || is_ios) {
         sources = [
           "task_queue_gcd.cc",
           "task_queue_posix.cc",
         ]
       }
       if (is_win) {
         sources = [
           "task_queue_win.cc",
@@ skipping 744 matching lines @@
       "java/src/org/webrtc/ContextUtils.java",
       "java/src/org/webrtc/Logging.java",
       "java/src/org/webrtc/Size.java",
       "java/src/org/webrtc/ThreadUtils.java",
     ]
 
     # TODO(sakal): Fix build hooks crbug.com/webrtc/8148
     no_build_hooks = true
   }
 }