Remove 'settings' type from gyp files

third_party/libpng/libpng.gyp

 # Copyright (c) 2009 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.
 
 {
   'variables': {
     'conditions': [
       [ 'os_posix == 1 and OS != "mac"', {
         # Link to system .so since we already use it due to GTK.
         'use_system_libpng%': 1,
@@ skipping 73 matching lines @@
           },
         }, {
           'variables': {
             'pkg-config': 'pkg-config'
           },
         }],
       ],
       'targets': [
         {
           'target_name': 'libpng',
-          'type': 'settings',
+          'type': 'none',
           'dependencies': [
             '../zlib/zlib.gyp:zlib',
           ],
           'direct_dependent_settings': {
             'cflags': [
               '<!@(<(pkg-config) --cflags libpng)',
             ],
             'defines': [
               'USE_SYSTEM_LIBPNG',
             ],
           },
           'link_settings': {
             'ldflags': [
               '<!@(<(pkg-config) --libs-only-L --libs-only-other libpng)',
             ],
             'libraries': [
               '<!@(<(pkg-config) --libs-only-l libpng)',
             ],
           },
         },
       ],
     }],
   ],
 }