GN: Fix Windows Clang errors

webrtc/examples/BUILD.gn

 # Copyright (c) 2016 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.
 
 if (is_android) {
   import("//build/config/android/config.gni")
@@ skipping 397 matching lines @@
     if (is_win) {
       sources += [
         "peerconnection/client/flagdefs.h",
         "peerconnection/client/main.cc",
         "peerconnection/client/main_wnd.cc",
         "peerconnection/client/main_wnd.h",
       ]
       cflags = [ "/wd4245" ]
       configs += [ "//build/config/win:windowed" ]
     }
+    if (is_win && is_clang) {
+      cflags = [
+        # Disable warnings failing when compiling with Clang on Windows.
+        # https://bugs.chromium.org/p/webrtc/issues/detail?id=5366
+        "-Wno-reorder",
+        "-Wno-unused-function",
+      ]
+    }
     if (is_linux) {
       sources += [
         "peerconnection/client/linux/main.cc",
         "peerconnection/client/linux/main_wnd.cc",
         "peerconnection/client/linux/main_wnd.h",
       ]
       libs = [
         "X11",
         "Xcomposite",
         "Xext",
@@ skipping 78 matching lines @@
       "//webrtc/system_wrappers:field_trial_default",
       "//webrtc/system_wrappers:metrics_default",
     ]
     if (is_clang) {
       # Suppress warnings from the Chromium Clang plugin.
       # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
       configs -= [ "//build/config/clang:find_bad_constructs" ]
     }
   }
 }