Delete unused class rtc::RegKey.

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 545 matching lines @@
       "transformadapter.h",
       "virtualsocketserver.cc",
       "virtualsocketserver.h",
       "window.h",
     ]
 
     if (is_win) {
       sources += [
         "diskcache_win32.cc",
         "diskcache_win32.h",
-        "win32regkey.cc",
-        "win32regkey.h",
         "win32socketinit.cc",
         "win32socketinit.h",
         "win32socketserver.cc",
         "win32socketserver.h",
       ]
     }
 
     if (rtc_build_json) {
       deps += [ "//third_party/jsoncpp" ]
     } else {
@@ skipping 188 matching lines @@
 
     deps = [
       "//base:base_java",
     ]
 
     data = [
       "//webrtc/build/android/test_runner.py",
     ]
   }
 }