make use of use_glib variable rather than is_linux when adding glib config

ui/base/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/ui.gni")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
@@ skipping 368 matching lines @@
 
   if (!use_aura || !is_linux) {
     sources -= [ "resource/resource_bundle_auralinux.cc" ]
   }
 
   if (use_aura && is_win) {
     sources -= [ "dragdrop/drag_utils_aura.cc" ]
   }
 
   if (is_linux) {
-    configs += [
-      "//build/config/linux:fontconfig",
-      "//build/config/linux:glib",
-    ]
+    configs += [ "//build/config/linux:fontconfig" ]
+  }
+
+  if (use_glib) {
+    configs += [ "//build/config/linux:glib" ]
   }
 
   if ((is_linux && !is_chromeos) || is_chromeos) {
     if (!toolkit_views && !use_aura) {
       sources -= [
         "dragdrop/drag_utils.cc",
         "dragdrop/drag_utils.h",
       ]
     }
   }
@@ skipping 450 matching lines @@
   }
   if (is_mac) {
     data += [ "$root_out_dir/ui_unittests Framework.framework/" ]
 
     if (is_asan && symbol_level == 0) {
       data += [ "$root_out_dir/ui_base_unittests.dSYM/" ]
     }
   }
 }
 # TODO(GYP) Mac (ui_base_tests_bundle)