Add precompiled headers to GN build for large targets.

net/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/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build/module_args/v8.gni")
 import("//url/config.gni")
 import("//testing/test.gni")
@@ skipping 60 matching lines @@
   defines = [
     # TODO(GYP) Note that the GYP file supports linux_link_kerberos (defaults to
     # 0) which implies that we run pkg_config on kerberos and link to that
     # rather than setting this define which will dynamically open it. That
     # doesn't seem to be set in the regular builds, so we're skipping this
     # capability here.
     "DLOPEN_KERBEROS",
     "NET_IMPLEMENTATION",
   ]
 
-  # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-  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",
+  ]
   public_configs = [ ":net_config" ]
   include_dirs = []
 
   public_deps = [
     ":net_quic_proto",
     "//crypto",
     "//crypto:platform",
     "//url",
   ]
   deps = [
@@ skipping 588 matching lines @@
     "test/url_request/url_request_mock_data_job.cc",
     "test/url_request/url_request_mock_data_job.h",
     "test/url_request/url_request_slow_download_job.cc",
     "test/url_request/url_request_slow_download_job.h",
     "url_request/test_url_fetcher_factory.cc",
     "url_request/test_url_fetcher_factory.h",
     "url_request/url_request_test_util.cc",
     "url_request/url_request_test_util.h",
   ]
 
-  # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-  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",
+  ]
 
   public_deps = [
     "//base",
     "//base/test:test_support",
     "//crypto",
     "//net",
     "//net/tools/tld_cleanup",
     "//testing/gmock",
     "//testing/gtest",
     "//url",
@@ skipping 602 matching lines @@
     "//third_party/protobuf:protobuf_lite",
   ]
 }
 
 # TODO(GYP) make this compile on Android, we need some native test deps done.
 # TODO(GYP) Also doesn't work on Mac, need to figure out why not.
 if (!is_android && !is_mac) {
   test("net_unittests") {
     sources = gypi_values.net_test_sources
 
-    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-    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",
+    ]
     defines = []
 
     deps = [
       ":balsa",
       ":extras",
       ":http_server",
       ":net",
       ":simple_quic_tools",
       ":test_support",
       "//base",
@@ skipping 334 matching lines @@
   } else {
     sources -= [ "proxy/proxy_resolver_perftest.cc" ]
   }
 
   if (is_win && icu_use_data_file) {
     # This is needed to trigger the dll copy step on windows.
     # TODO(mark): Specifying this here shouldn't be necessary.
     deps += [ "//third_party/icu:icudata" ]
   }
 }