Rearrange dependency to enable adding finch experiment in webrtc

third_party/libjingle/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/crypto.gni")
 import("//build/config/features.gni")
 
 # From third_party/libjingle/libjingle.gyp's target_defaults.
 config("jingle_unexported_configs") {
   defines = [
@@ skipping 278 matching lines @@
 
 if (enable_webrtc) {
   source_set("libjingle_webrtc") {
     sources = [
       "overrides/init_webrtc.cc",
       "overrides/init_webrtc.h",
     ]
     configs += [ ":jingle_unexported_configs" ]
     public_configs = [ ":jingle_public_configs" ]
     deps = [
-      ":libjingle_webrtc_common",
+      ":libjingle_webrtc_shared",
+    ]
+  }
+
+  source_set("libjingle_webrtc_common") {
+    system_wrappers_dir = "../webrtc/system_wrappers"
+    sources = [
+      "$system_wrappers_dir/interface/field_trial_default.h",
+      "$system_wrappers_dir/interface/field_trial.h",
+      "$system_wrappers_dir/source/field_trial_default.cc",
+    ]
+    deps = [
+      ":libjingle_webrtc_shared",
     ]
   }
 
   # Note: this does not support the shared library build of libpeerconnection
   # as is supported in the GYP build. It's not clear what this is used for.
-  source_set("libjingle_webrtc_common") {
+  source_set("libjingle_webrtc_shared") {
     sources = [
       "overrides/talk/media/webrtc/webrtcexport.h",
       "source/talk/app/webrtc/audiotrack.cc",
       "source/talk/app/webrtc/audiotrack.h",
       "source/talk/app/webrtc/datachannel.cc",
       "source/talk/app/webrtc/datachannel.h",
       "source/talk/app/webrtc/dtlsidentitystore.cc",
       "source/talk/app/webrtc/dtlsidentitystore.h",
       "source/talk/app/webrtc/dtmfsender.cc",
       "source/talk/app/webrtc/dtmfsender.h",
@@ skipping 165 matching lines @@
     ]
 
     configs += [ ":jingle_unexported_configs" ]
     public_configs = [ ":jingle_public_configs" ]
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [ "//build/config/compiler:no_chromium_code" ]
 
     deps = [
       # TODO(GYP): crbug.com/481633. Consider depending on :libjingle_webrtc
       # instead.
-      ":libjingle_webrtc_common",
+      ":libjingle_webrtc_shared",
       "//third_party/webrtc",
-      "//third_party/webrtc/system_wrappers",
       "//third_party/webrtc/voice_engine",
     ]
   }
 
   source_set("libstunprober") {
     p2p_dir = "../webrtc/p2p"
     sources = [
       "$p2p_dir/stunprober/stunprober.cc",
     ]
 
     deps = [
       "//third_party/webrtc/base:rtc_base",
-      ":libjingle_webrtc_common",
+      ":libjingle_webrtc_shared",
     ]
   }
 }  # enable_webrtc
 # TODO(GYP): Port libjingle.gyp's enable_webrtc condition block.