Un-nest configs in GN files.

third_party/libwebp/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/arm.gni")
 
 config("libwebp_config") {
   include_dirs = [ "." ]
 }
 
@@ skipping 144 matching lines @@
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
 
   all_dependent_configs = [ ":libwebp_config" ]
 
   deps = [
     ":libwebp_utils",
   ]
 }
 
+config("libwebp_utils_warnings") {
+  if (is_clang) {
+    # See https://code.google.com/p/webp/issues/detail?id=253.
+    cflags = [ "-Wno-incompatible-pointer-types" ]
+  }
+}
+
 source_set("libwebp_utils") {
   sources = [
     "utils/bit_reader.c",
     "utils/bit_writer.c",
     "utils/color_cache.c",
     "utils/filters.c",
     "utils/huffman.c",
     "utils/huffman_encode.c",
     "utils/quant_levels.c",
     "utils/quant_levels_dec.c",
     "utils/random.c",
     "utils/rescaler.c",
     "utils/thread.c",
     "utils/utils.c",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
 
   all_dependent_configs = [ ":libwebp_config" ]
 
-  config("libwebp_utils_warnings") {
-    if (is_clang) {
-      # See https://code.google.com/p/webp/issues/detail?id=253.
-      cflags = [ "-Wno-incompatible-pointer-types" ]
-    }
-  }
   public_configs = [ ":libwebp_utils_warnings" ]
 }
 
 group("libwebp") {
   deps = [
     ":libwebp_dec",
     ":libwebp_demux",
     ":libwebp_dsp",
     ":libwebp_enc",
     ":libwebp_utils",
   ]
   public_configs = [ ":libwebp_config" ]
   if (use_dsp_neon) {
     deps += [ ":libwebp_dsp_neon" ]
   }
 }