Add precompiled headers to GN build for large targets.

content/common/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("//build/config/ui.gni")
 import("//content/common/common.gni")
 import("//third_party/mojo/src/mojo/public/tools/bindings/mojom.gni")
 
 if (is_chromeos && current_cpu != "arm") {
@@ skipping 114 matching lines @@
   # Only the public target should depend on this. All other targets (even
   # internal content ones) should depend on the public one.
   visibility = [ "//content/public/common:common_sources" ]
 
   sources = rebase_path(content_common_gypi_values.private_common_sources,
                         ".",
                         "//content")
 
   configs += [
     "//content:content_implementation",
+    "//build/config:precompiled_headers",
     "//build/config/compiler:no_size_t_to_int_warning",
   ]
 
   public_deps = [
     "//gpu/command_buffer/common",
     "//third_party/WebKit/public:blink_headers",
   ]
   deps = [
     "//base",
     "//build/util:webkit_version",
@@ skipping 360 matching lines @@
 
   import_dirs = [ "//mojo/services" ]
 
   deps = [
     "//content/public/common:mojo_bindings",
     "//mojo/application/public/interfaces",
     "//skia/public/interfaces",
     "//ui/mojo/geometry:interfaces",
   ]
 }