Revert of [Sync] Merge sync_unit_tests into components_unit_tests.

components/sync/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/features.gni")
 import("//components/sync/protocol/protocol_sources.gni")
 import("//testing/test.gni")
 
 component("sync") {
   public_deps = [
@@ skipping 591 matching lines @@
 
   defines = [ "SYNC_TEST" ]
 
   public_deps = [
     "//base",
     "//components/sync",
     "//testing/gmock",
   ]
 }
 
-source_set("unit_tests") {
-  testonly = true
+# GYP version: sync/sync_tests.gypi:sync_unit_tests
+test("sync_unit_tests") {
   sources = [
     "api/attachments/attachment_id_unittest.cc",
     "api/attachments/attachment_metadata_unittest.cc",
     "api/attachments/attachment_unittest.cc",
     "api/entity_data_unittest.cc",
     "api/model_type_service_unittest.cc",
     "api/sync_change_unittest.cc",
     "api/sync_data_unittest.cc",
     "api/sync_error_unittest.cc",
     "api/sync_merge_result_unittest.cc",
@@ skipping 81 matching lines @@
     "//third_party/pywebsocket/",
     "//third_party/tlslite/",
     "$root_out_dir/pyproto/google/",
   ]
 
   deps = [
     ":test_support_sync_api",
     ":test_support_sync_core",
     ":test_support_sync_core_impl",
     "//base",
+    "//base/test:run_all_unittests",
     "//components/sync",
     "//components/sync/protocol",
     "//google_apis",
     "//google_apis:test_support",
     "//net",
     "//net:test_support",
     "//sql",
     "//sql:test_support",
     "//testing/gmock",
     "//testing/gtest",
@@ skipping 164 matching lines @@
       ":fake_server_jni",
       ":sync_core",
       ":test_support_sync_fake_server",
       "//base",
       "//components/sync/protocol:protocol",
       "//testing/gtest",
       "//url:url",
     ]
   }
 }