Add base to "gn check".

base/allocator/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/allocator.gni")
 
 declare_args() {
   # Provide a way to force disable debugallocation in Debug builds,
   # e.g. for profiling (it's more rare to profile Debug builds,
   # but people sometimes need to do that).
@@ skipping 72 matching lines @@
     source_set("allocator_shim") {
       sources = [
         "allocator_shim_win.cc",
       ]
       configs -= [ "//build/config/compiler:chromium_code" ]
       configs += [ "//build/config/compiler:no_chromium_code" ]
 
       public_configs = [ ":nocmt" ]
       deps = [
         ":prep_libc",
+        "//base",
       ]
     }
   }
 }
 
 if (use_allocator == "tcmalloc") {
   # tcmalloc currently won't compile on Android.
   source_set("tcmalloc") {
     tcmalloc_dir = "//third_party/tcmalloc/chromium"
 
@@ skipping 195 matching lines @@
     }
 
     deps += [ "//base/third_party/dynamic_annotations" ]
 
     if (is_win) {
       ldflags = [ "/ignore:4006:4221" ]
     }
   }
 }  # !is_android
 
-source_set("allocator_extension_thunks") {
+source_set("extension_thunks") {
   visibility = [ "//base/*" ]
   sources = [
     "allocator_extension_thunks.cc",
     "allocator_extension_thunks.h",
   ]
   if (is_android && !is_debug) {
     configs -= [ "//build/config/compiler:default_optimization" ]
     configs += [ "//build/config/compiler:optimize_max" ]
   }
 }