GN: Fix windows clang errors. Attempt 2.

third_party/winsdk_samples/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.
 
 if (is_win) {
   baseclasses_dir = "src/Samples/multimedia/directshow/baseclasses"
 
   config("winsdk_samples_config") {
     include_dirs = [ baseclasses_dir ]
   }
 
+  config("winsdk_samples_warnings_config") {
+    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-comment",
+        "-Wno-delete-non-virtual-dtor",
+        "-Wno-ignored-attributes",
+        "-Wno-logical-op-parentheses",
+        "-Wno-non-pod-varargs",
+        "-Wno-microsoft-extra-qualification",
+        "-Wno-missing-braces",
+        "-Wno-overloaded-virtual",
+        "-Wno-parentheses",
+        "-Wno-reorder",
+        "-Wno-string-conversion",
+        "-Wno-tautological-constant-out-of-range-compare",
+        "-Wno-unused-private-field",
+        "-Wno-writable-strings",
+      ]
+    }
+  }
+
   static_library("winsdk_samples") {
     sources = [
       "$baseclasses_dir/amextra.cpp",
       "$baseclasses_dir/amextra.h",
       "$baseclasses_dir/amfilter.cpp",
       "$baseclasses_dir/amfilter.h",
       "$baseclasses_dir/amvideo.cpp",
       "$baseclasses_dir/cache.h",
       "$baseclasses_dir/combase.cpp",
       "$baseclasses_dir/combase.h",
@@ skipping 51 matching lines @@
       "$baseclasses_dir/wxutil.cpp",
       "$baseclasses_dir/wxutil.h",
     ]
 
     public_configs = [ ":winsdk_samples_config" ]
 
     configs -= [
       "//build/config/compiler:chromium_code",
       "//build/config/win:nominmax",
     ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    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-comment",
-        "-Wno-delete-non-virtual-dtor",
-        "-Wno-ignored-attributes",
-        "-Wno-logical-op-parentheses",
-        "-Wno-non-pod-varargs",
-        "-Wno-microsoft-extra-qualification",
-        "-Wno-missing-braces",
-        "-Wno-overloaded-virtual",
-        "-Wno-parentheses",
-        "-Wno-reorder",
-        "-Wno-string-conversion",
-        "-Wno-tautological-constant-out-of-range-compare",
-        "-Wno-unused-private-field",
-        "-Wno-writable-strings",
-      ]
-    }
+    configs += [
+      "//build/config/compiler:no_chromium_code",
+      ":winsdk_samples_warnings_config",
+    ]
   }
 }