Add precompiled headers to GN build for large targets.

gpu/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.
 
 # GYP-to-GN project mappings:
 #
 #  gpu.gyp:command_buffer_client => //gpu/command_buffer/client
 #
 #  gpu.gyp:command_buffer_common => //gpu/command_buffer/common
 #
@@ skipping 213 matching lines @@
     "config/gpu_control_list_unittest.cc",
     "config/gpu_control_list_version_info_unittest.cc",
     "config/gpu_driver_bug_list_unittest.cc",
     "config/gpu_info_collector_unittest.cc",
     "config/gpu_info_unittest.cc",
     "config/gpu_test_config_unittest.cc",
     "config/gpu_test_expectations_parser_unittest.cc",
     "config/gpu_util_unittest.cc",
   ]
 
-  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
+  configs += [
+    "//build/config:precompiled_headers",
+
+    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+    "//build/config/compiler:no_size_t_to_int_warning",
+  ]
 
   deps = [
     ":gpu",
     ":test_support",
     "//base",
     "//base/test:test_support",
     "//base/third_party/dynamic_annotations",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/angle:translator",
@@ skipping 44 matching lines @@
 
   deps = [
     "//base",
     "//base/test:test_support",
     "//base/third_party/dynamic_annotations",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/angle:translator_static",
   ]
 }