GN: Fix compilation with NaCl toolchain

webrtc/modules/desktop_capture/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/ui.gni")
 import("../../build/webrtc.gni")
@@ skipping 109 matching lines @@
     libs = [
       "AppKit.framework",
       "IOKit.framework",
       "OpenGL.framework",
     ]
   }
 
   configs += [ "../..:common_config" ]
   public_configs = [ "../..:common_inherited_config" ]
 
-  if (is_clang) {
+  if (is_clang && !is_nacl) {
     # Suppress warnings from Chrome's Clang plugins.
     # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
     configs -= [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps = [
     ":primitives",
     "../../base:rtc_base_approved",
     "../../system_wrappers",
   ]
@@ skipping 14 matching lines @@
     ]
 
     configs += [ "../..:common_config" ]
     public_configs = [ "../..:common_inherited_config" ]
 
     if (is_posix && !is_mac) {
       cflags = [ "-msse2" ]
     }
   }
 }