Broke out 'level_indicator' of the voice_engine GN target.

webrtc/voice_engine/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/webrtc.gni")
 import("//testing/test.gni")
@@ skipping 11 matching lines @@
     "include/voe_codec.h",
     "include/voe_errors.h",
     "include/voe_external_media.h",
     "include/voe_file.h",
     "include/voe_hardware.h",
     "include/voe_neteq_stats.h",
     "include/voe_network.h",
     "include/voe_rtp_rtcp.h",
     "include/voe_video_sync.h",
     "include/voe_volume_control.h",
-    "level_indicator.cc",
-    "level_indicator.h",
     "monitor_module.cc",
     "monitor_module.h",
     "network_predictor.cc",
     "network_predictor.h",
     "output_mixer.cc",
     "output_mixer.h",
     "shared_data.cc",
     "shared_data.h",
     "statistics.cc",
     "statistics.h",
@@ skipping 40 matching lines @@
   configs += [ "..:common_config" ]
   public_configs = [ "..:common_inherited_config" ]
 
   if (is_clang) {
     # Suppress warnings from Chrome's Clang plugins.
     # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
     configs -= [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps = [
+    ":level_indicator",
     "..:rtc_event_log",
     "..:webrtc_common",
     "../base:rtc_base_approved",
     "../common_audio",
     "../modules/audio_coding",
     "../modules/audio_conference_mixer",
     "../modules/audio_device",
     "../modules/audio_processing",
     "../modules/bitrate_controller",
     "../modules/media_file",
     "../modules/pacing",
     "../modules/rtp_rtcp",
     "../modules/utility",
     "../system_wrappers",
   ]
 }
 
+source_set("level_indicator") {
+  sources = [
+    "level_indicator.cc",
+    "level_indicator.h",
+  ]
+
+  configs += [ "..:common_config" ]
+  public_configs = [ "..:common_inherited_config" ]
+
+  deps = [
+    "..:webrtc_common",
+    "../base:rtc_base_approved",
+    "../common_audio",
+  ]
+}
+
 if (rtc_include_tests) {
   test("voice_engine_unittests") {
     deps = [
       ":voice_engine",
       "//testing/gmock",
       "//testing/gtest",
       "//webrtc/common_audio",
       "//webrtc/modules/audio_coding",
       "//webrtc/modules/audio_conference_mixer",
       "//webrtc/modules/audio_device",
@@ skipping 125 matching lines @@
       }
 
       if (is_clang) {
         # Suppress warnings from Chrome's Clang plugins.
         # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
         configs -= [ "//build/config/clang:find_bad_constructs" ]
       }
     }
   }
 }