Audit GN cflags and defines to match GYP build.

chrome/test/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")
 import("//build/config/ui.gni")
 import("//build/module_args/v8.gni")
 import("//testing/test.gni")
 
@@ skipping 165 matching lines @@
     deps += [ "//pdf" ]
   }
 
   if (use_ash) {
     deps += [ "//ash:test_support" ]
   }
   if (toolkit_views) {
     deps += [ "//ui/views:test_support" ]
   }
 
-  if (enable_background) {
-    defines += [ "ENABLE_BACKGROUND=1" ]
-  }
-
   if (enable_extensions) {
     deps += [
       "//chrome/common/extensions/api",
       "//extensions:test_support",
     ]
   }
 }
 
 source_set("test_support_unit") {
   testonly = true
@@ skipping 1480 matching lines @@
     }
     if (use_ozone) {
       # crbug.com/354036
       sources -= [ "../browser/chromeos/events/event_rewriter_unittest.cc" ]
     }
     if (!enable_plugin_installation) {
       sources -= [ "../browser/plugins/plugin_installer_unittest.cc" ]
     }
   }
 }