Do not run discardable memory related browser test for official build.

content/test/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/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
@@ skipping 878 matching lines @@
   if (enable_web_speech) {
     sources += [ "../browser/speech/speech_recognition_browsertest.cc" ]
   }
 
   if (!is_chrome_branded) {
     # These tests depend on single process mode, which is disabled
     # in official builds.
     sources += [
       "../renderer/browser_render_view_browsertest.cc",
       "../renderer/dom_serializer_browsertest.cc",
+      "../renderer/render_thread_impl_discardable_memory_browsertest.cc",
       "../renderer/resource_fetcher_browsertest.cc",
       "../renderer/savable_resources_browsertest.cc",
     ]
 
     deps += [
       "//components/discardable_memory/client",
       "//components/discardable_memory/common",
       "//components/discardable_memory/service",
     ]
   }
@@ skipping 817 matching lines @@
   if (is_android) {
     deps += [ "//testing/android/native_test:native_test_native_code" ]
   }
 }
 
 group("fuzzers") {
   deps = [
     "//content/test/fuzzer",
   ]
 }