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

ipc/BUILD.gn

 # Copyright (c) 2012 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/nacl/config.gni")
 import("//testing/test.gni")
 
 component("ipc") {
   sources = [
     "attachment_broker.cc",
@@ skipping 126 matching lines @@
 }
 
 # This is provided as a separate target so other targets can provide param
 # traits implementations without necessarily linking to all of IPC.
 source_set("param_traits") {
   public = [
     "ipc_param_traits.h",
   ]
 }
 
+group("ipc_tests_run") {
+  testonly = true
+  deps = [
+    ":ipc_tests",
+  ]
+}
+
 test("ipc_tests") {
   sources = [
     "attachment_broker_mac_unittest.cc",
     "attachment_broker_privileged_mac_unittest.cc",
     "attachment_broker_privileged_win_unittest.cc",
     "ipc_channel_posix_unittest.cc",
     "ipc_channel_proxy_unittest.cc",
     "ipc_channel_reader_unittest.cc",
     "ipc_channel_unittest.cc",
     "ipc_fuzzing_tests.cc",
@@ skipping 78 matching lines @@
   ]
   public_deps = [
     ":ipc",
   ]
   deps = [
     "//base",
     "//base/test:test_support",
     "//testing/gtest",
   ]
 }