Revert "Add precompiled headers to GN build for large targets."

chrome/common/extensions/api/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/json_schema_api.gni")
 import("schemas.gni")
 
 assert(enable_extensions)
 
 # GYP version: chrome/common/extensions/api/api.gyp:chrome_api
 json_schema_api("api") {
   schemas = true
   bundle = true
-  configs = [ "//build/config:precompiled_headers" ]
   bundle_name = "Chrome"
 
   deps = schema_dependencies
 }
 
 # GYP version: chrome/browser/extensions/api/api.gyp:chrome_api_registration
 json_schema_api("api_registration") {
   impl_dir = "//chrome/browser/extensions/api"
   bundle_registration = true
-  configs = [ "//build/config:precompiled_headers" ]
   bundle_name = "Chrome"
 
   deps = [
     # Different APIs include headers from these targets.
     "//content/public/browser",
     "//extensions/browser",
 
     # Different APIs include some headers from chrome/common that in turn
     # include generated headers from these targets.
     # TODO(brettw) this should be made unnecessary if possible.
     ":api",
     "//components/copresence/proto",
     "//components/metrics/proto",
     "//skia",
     "//sync",
     "//ui/accessibility:ax_gen",
   ]
   if (is_chromeos) {
     # deps += [ "<(DEPTH)/chrome/chrome.gyp:drive_proto" ]  TODO(GYP)
   }
   deps += schema_dependencies
 
   # This must be a static library because the generated schemas have
   # dependencies into both the browser and child processes, and this won't link
   # in the multi DLL build. In the child DLL, only some files are needed, and
   # these have no dependencies into the browser, so a static library solves the
   # problem.
   generate_static_library = true
 }