[Sync] Fix test support targets + duplicate namespaces.

components/browsing_data/core/BUILD.gn

 # Copyright 2016 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.
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
 static_library("core") {
   sources = [
@@ skipping 42 matching lines @@
     "browsing_data_utils_unittest.cc",
     "history_notice_utils_unittest.cc",
   ]
 
   deps = [
     ":core",
     "//base",
     "//components/autofill/core/browser:browser",
     "//components/history/core/test:test",
     "//components/signin/core/browser:test_support",
-    "//components/sync:test_support_sync_driver",
-    "//components/sync/protocol:protocol",
+    "//components/sync",
+    "//components/sync:test_support_driver",
     "//components/version_info:version_info",
     "//net",
     "//testing/gtest",
   ]
 }