Remove .def files from GYP and GN in webrtc/base

webrtc/base/base.gyp

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 {
   'includes': [ '../build/common.gypi', ],
@@ skipping 415 matching lines @@
                 'dbus.h',
                 'libdbusglibsymboltable.cc',
                 'libdbusglibsymboltable.h',
                 'linuxfdwalk.c',
                 'linuxfdwalk.h',
               ],
             }],
             ['os_posix==1', {
               'sources': [
                 'latebindingsymboltable.cc',
-                'latebindingsymboltable.cc.def',
                 'latebindingsymboltable.h',
-                'latebindingsymboltable.h.def',
                 'posix.cc',
                 'posix.h',
               ],
             }],
             ['OS=="mac"', {
               'sources': [
                 'macasyncsocket.cc',
                 'macasyncsocket.h',
                 'maccocoasocketserver.h',
                 'maccocoasocketserver.mm',
@@ skipping 192 matching lines @@
     },
     {
      'target_name': 'gtest_prod',
       'type': 'static_library',
       'sources': [
         'gtest_prod_util.h',
       ],
     },
   ],
 }