Remove flag needed by outdated libpng

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 107 matching lines @@
         [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris"]', {
           'dependencies': [
             'libpng.gyp:libpng',
           ],
           # end libpng stuff
         }],
         [ 'skia_os == "android"', {
           'include_dirs': [
              '../src/utils',
           ],
-          'cflags' : [
-            # SkImageDecoder_libpng includes png.h.
-            # In the version of libpng that we use on Android (1.2.46),
-            # there is a missing space between a literal and an identifier
-            # in png.h, triggering a warning in C++11.
-            '-Wno-literal-suffix',
-          ],
           'dependencies': [
             'libpng.gyp:libpng',
           ],
           '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/SkImageDecoder_pkm.cpp',
                 '../src/images/SkImageDecoder_ktx.cpp',
@@ skipping 14 matching lines @@
         }],
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '../include/images',
         ],
       },
     },
   ],
 }