Delete ChromeOS code

gyp/images.gyp

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # GYP file for images project.
 {
   'targets': [
     {
       'target_name': 'images',
@@ skipping 89 matching lines @@
           'conditions': [
             [ 'skia_android_framework == 1', {
               # The android framework disables these decoders as they are of little use to
               # Java applications that can't take advantage of the compressed formats.
               'sources!': [
                 '../src/images/SkKTXImageEncoder.cpp',
               ],
             }],
           ],
         }],
-        [ 'skia_os == "chromeos"', {
-          'dependencies': [
-            'libpng.gyp:libpng',
-          ],
-        }],
         [ 'skia_os == "ios"', {
            'include_dirs': [
              '../include/utils/mac',
            ],
         }],
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '../include/images',
         ],
       },
     },
   ],
 }