Fix //media:media_unittests for gn

media/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/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/features.gni")
 import("//build/config/linux/pkg_config.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
@@ skipping 14 matching lines @@
   }
   if (use_pulseaudio) {
     defines += [ "USE_PULSEAUDIO" ]
     if (!link_pulseaudio) {
       defines += [ "DLOPEN_PULSEAUDIO" ]
     }
   }
   if (use_cras) {
     defines += [ "USE_CRAS" ]
   }
+  if (use_alsa) {
+    defines += [ "USE_ALSA" ]
+  }
 }
 
 config("media_dependent_config") {
   defines = []
   if (!media_use_libvpx) {
     defines += [ "MEDIA_DISABLE_LIBVPX" ]
   }
   if (!media_use_ffmpeg) {
     defines += [ "MEDIA_DISABLE_FFMPEG" ]
   }
@@ skipping 300 matching lines @@
 
   if (current_cpu != "arm" && is_chromeos) {
     sources += [
       "filters/h264_bitstream_buffer.cc",
       "filters/h264_bitstream_buffer.h",
     ]
   }
 
   if (use_alsa) {
     libs += [ "asound" ]
-    defines += [ "USE_ALSA" ]
     sources += [
       "midi/midi_manager_alsa.cc",
       "midi/midi_manager_alsa.h",
     ]
   }
 
   # A simple WebM encoder for animated avatars on ChromeOS.
 
   if (use_ozone) {
     # Used for the generated listing header (ui/ozone/platform_list.h)
@@ skipping 430 matching lines @@
     deps = [
       ":media",
       ":shared_memory_support",
       "//base",
       "//ui/gl",
       "//ui/gfx",
       "//ui/gfx/geometry",
     ]
   }
 }