use more specific variables in net/BUILD.gn

net/BUILD.gn

 # Copyright (c) 2013 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")
 import("//build/config/ui.gni")
 import("//build/module_args/v8.gni")
 import("//url/config.gni")
 import("//testing/test.gni")
@@ skipping 989 matching lines @@
       sources = [
         "tools/net_watcher/net_watcher.cc",
       ]
       deps = [
         ":net",
         ":net_with_v8",
         "//base",
       ]
 
       if (is_desktop_linux) {
-        configs += [
-          "//build/config/linux:gconf",
-          "//build/config/linux:glib",
-        ]
         deps += [ "//build/config/linux:gio" ]
       }
+
+      if (use_gconf) {
+        configs += [ "//build/config/linux:gconf" ]
+      }
+
+      if (use_glib) {
+        configs += [ "//build/config/linux:glib" ]
+      }
     }
   }
 
   executable("run_testserver") {
     testonly = true
     sources = [
       "tools/testserver/run_testserver.cc",
     ]
     deps = [
       ":test_support",
@@ skipping 660 matching lines @@
   if (enable_websockets) {
     sources += [ "websockets/websocket_frame_perftest.cc" ]
   }
 
   if (use_v8_in_net) {
     deps += [ ":net_with_v8" ]
   } else {
     sources -= [ "proxy/proxy_resolver_perftest.cc" ]
   }
 }