mandoline sandbox: prewarm libraries before we raise the sandbox.

mandoline/app/desktop/BUILD.gn

 # Copyright 2015 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.
 
 group("desktop") {
   deps = [
     ":mandoline",
   ]
 }
 
 executable("mandoline") {
   sources = [
     "../core_services_initialization.cc",
     "launcher_process.cc",
     "launcher_process.h",
     "main.cc",
   ]
 
   deps = [
     "//base",
     "//build/config/sanitizers:deps",
     "//components/tracing:startup_tracing",
     "//mojo/common",
     "//mojo/environment:chromium",
     "//mojo/runner:lib",
   ]
 
-  if (is_linux && !is_android) {
-    sources += [
-      "linux_sandbox.cc",
-      "linux_sandbox.h",
-    ]
-
-    deps += [ "//sandbox/linux:sandbox" ]
-  }
-
   data_deps = [
     "//components/html_viewer",
     "//mandoline/services/core_services",
     "//mandoline/services/updater",
     "//mandoline/ui",
   ]
 }