Move gn _run target generation into test().

blimp/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/ui.gni")
 import("//testing/test.gni")
 
 # Convenience meta-target for all of Blimp's production & test code.
 group("blimp") {
   # In spite of the name, this really just means that non-test targets
@@ skipping 40 matching lines @@
   deps = [
     "//blimp/client:feature_unit_tests",
     "//blimp/common:unit_tests",
     "//blimp/net:unit_tests",
   ]
 
   if (is_linux) {
     deps += [ "//blimp/engine:unit_tests" ]
   }
 }
-
-# TODO(GYP): Delete this after we've converted everything to GN.
-# The _run targets exist only for compatibility w/ GYP.
-group("blimp_unittests_run") {
-  testonly = true
-  deps = [
-    ":blimp_unittests",
-  ]
-}