Get rid of SCHANNEL code.

webrtc/base/BUILD.gn

 # 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.
 
 import("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 519 matching lines @@
 
     all_dependent_configs = [ ":mac_config" ]
 
     if (current_cpu == "x86") {
       all_dependent_configs += [ ":mac_x86_config" ]
     }
   }
 
   if (is_win) {
     sources += [
-      "schanneladapter.cc",
-      "schanneladapter.h",
       "win32.cc",
       "win32.h",
       "win32filesystem.cc",
       "win32filesystem.h",
       "win32securityerrors.cc",
       "win32window.cc",
       "win32window.h",
       "win32windowpicker.cc",
       "win32windowpicker.h",
       "winfirewall.cc",
@@ skipping 33 matching lines @@
       "linux.cc",
       "linux.h",
     ]
   }
 
   if (is_nacl) {
     deps += [ "//native_client_sdk/src/libraries/nacl_io" ]
     defines += [ "timezone=_timezone" ]
   }
 }