Revert of Move gn _run target generation into test().

media/midi/BUILD.gn

 # Copyright 2015 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/features.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
 import("//testing/test.gni")
 
@@ skipping 132 matching lines @@
       "midi_manager_alsa.cc",
       "midi_manager_alsa.h",
     ]
   }
 
   if (use_udev) {
     deps += [ "//device/udev_linux" ]
   }
 }
 
+# TODO(GYP): Delete this after we've converted everything to GN.
+# The _run targets exist only for compatibility w/ GYP.
+group("midi_unittests_run") {
+  testonly = true
+  deps = [
+    ":midi_unittests",
+  ]
+}
+
 test("midi_unittests") {
   sources = [
     "midi_manager_unittest.cc",
     "midi_manager_usb_unittest.cc",
     "midi_message_queue_unittest.cc",
     "midi_message_util_unittest.cc",
     "usb_midi_descriptor_parser_unittest.cc",
     "usb_midi_input_stream_unittest.cc",
     "usb_midi_output_stream_unittest.cc",
   ]
@@ skipping 20 matching lines @@
   }
 
   if (use_alsa && use_udev) {
     sources += [ "midi_manager_alsa_unittest.cc" ]
   }
 
   if (use_x11) {
     deps += [ "//tools/xdisplaycheck" ]
   }
 }