Remove som GYP annotations, remove unused manifest.

base/test/BUILD.gn

 # Copyright (c) 2013 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("//build/config/nacl/config.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
 static_library("test_config") {
   testonly = true
   sources = [
     "test_switches.cc",
     "test_switches.h",
     "test_timeouts.cc",
     "test_timeouts.h",
   ]
   deps = [
     "//base",
   ]
 }
 
-# GYP: //base/base.gyp:test_support_base
 static_library("test_support") {
   testonly = true
   sources = [
     "../trace_event/trace_config_memory_test_util.h",
     "android/java_handler_thread_for_testing.cc",
     "android/java_handler_thread_for_testing.h",
     "android/test_system_message_handler_link_android.cc",
     "android/test_system_message_handler_link_android.h",
     "fuzzed_data_provider.cc",
     "fuzzed_data_provider.h",
@@ skipping 282 matching lines @@
 if (is_android) {
   generate_jni("base_unittests_jni_headers") {
     sources = [
       "android/java/src/org/chromium/base/ContentUriTestUtils.java",
       "android/java/src/org/chromium/base/TestSystemMessageHandler.java",
       "android/java/src/org/chromium/base/TestUiThread.java",
     ]
     jni_package = "base"
   }
 }