Remove the code added to make extensions compile on Aura Android.

chrome/browser/extensions/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")
 
 assert(enable_extensions)
 
 gypi_values =
@@ skipping 87 matching lines @@
     ]
   } else {
     sources += [
       "default_apps.cc",
       "default_apps.h'",
     ]
     sources +=
         rebase_path(gypi_values.chrome_browser_extensions_non_chromeos_sources,
                     ".",
                     "//chrome")
-    if (is_android) {
-      sources -= [ "api/messaging/native_process_launcher_posix.cc" ]
-    }
   }
 
   if (enable_service_discovery) {
     sources += rebase_path(
             gypi_values.chrome_browser_extensions_service_discovery_sources,
             ".",
             "//chrome")
   }
 
   if (use_ash) {
@@ skipping 102 matching lines @@
                     "//chrome")
   }
 
   if (is_chromeos && use_ozone) {
     sources -= [ "global_shortcut_listener_chromeos.cc" ]
   }
   if (!use_ozone) {
     sources -= [ "global_shortcut_listener_ozone.cc" ]
   }
 }