Fix png encoding in skia debugger

gyp/debugger.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.
 {
   'variables': {
     'skia_warnings_as_errors': 0,
     'conditions': [
       [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris"]', {
         # Use the systemwide Qt libs by default
@@ skipping 122 matching lines @@
         '<(moc_gen_dir)/moc_SkInspectorWidget.cpp',
         '<(moc_gen_dir)/moc_SkSettingsWidget.cpp',
         '<(moc_gen_dir)/moc_SkRasterWidget.cpp',
         '<(moc_gen_dir)/moc_SkGLWidget.cpp',
       ],
       'dependencies': [
         'debugger_qt_mocs',
         'skia_lib.gyp:skia_lib',
         'jsoncpp.gyp:jsoncpp',
         'libpng.gyp:libpng',
+        'tools.gyp:picture_utils',
         'tools.gyp:url_data_manager',
       ],
       'cflags': [
         # Clang gets confused by QWeakPointer, see http://llvm.org/bugs/show_bug.cgi?id=13127
         '-Wno-uninitialized',
       ],
       'link_settings': {
         'libraries': [
           '<@(qt_libs)',
         ],
@@ skipping 18 matching lines @@
           'outputs': [ '<(moc_gen_dir)/moc_<(RULE_INPUT_ROOT).cpp' ],
           'action': [ '<(qt_moc)', '-DSK_SUPPORT_GPU=<(skia_gpu)',
                       '<(RULE_INPUT_PATH)',
                       '-o', '<(moc_gen_dir)/moc_<(RULE_INPUT_ROOT).cpp' ],
           'message': 'Generating <(RULE_INPUT_ROOT).cpp.',
         },
       ],
     },
   ],
 }