Roll Skia to r14226.

skia/skia_gn_files.gypi

 # This file is read into the GN build.
 
 # Files are relative to third_party/skia.
 {
   # Shared defines for all builds.
   'skia_feature_defines': [
     'GR_GL_CUSTOM_SETUP_HEADER="GrGLConfig_chrome.h"',
     'GR_GL_IGNORE_ES3_MSAA=0',
     'SK_ATTR_DEPRECATED=SK_NOTHING_ARG1',
     'SK_DEFERRED_CANVAS_USES_FACTORIES=1',
     'SK_DISABLE_OFFSETIMAGEFILTER_OPTIMIZATION',
     'SK_ENABLE_INST_COUNT=0',
     'SK_ENABLE_LEGACY_API_ALIASING=1',
     'SK_HIGH_QUALITY_IS_LANCZOS',
     'SK_IGNORE_BLURRED_RRECT_OPT',
     'SK_IGNORE_QUAD_RR_CORNERS_OPT',
     'SK_SUPPORT_LEGACY_GETCLIPTYPE',
     'SK_SUPPORT_LEGACY_GETTOPDEVICE',
     'SK_SUPPORT_LEGACY_GETTOTALCLIP',
     'SK_SUPPORT_LEGACY_LAYERRASTERIZER_API=1',
     'SK_SUPPORT_LEGACY_N32_NAME',
+    'SK_SUPPORT_LEGACY_PROCXFERMODE',
     'SK_SUPPORT_LEGACY_PUBLICEFFECTCONSTRUCTORS=1',
     'SK_USE_DISCARDABLE_SCALEDIMAGECACHE',
     'SK_WILL_NEVER_DRAW_PERSPECTIVE_TEXT',
   ],
 
   'skia_gpu_sources': [
     '<(skia_include_path)/gpu/GrBackendEffectFactory.h',
     '<(skia_include_path)/gpu/GrClipData.h',
     '<(skia_include_path)/gpu/GrColor.h',
     '<(skia_include_path)/gpu/GrConfig.h',
@@ skipping 841 matching lines @@
     '<(skia_src_path)/utils/win/SkDWriteGeometrySink.h',
     '<(skia_src_path)/utils/win/SkHRESULT.cpp',
     '<(skia_src_path)/utils/win/SkIStream.cpp',
     '<(skia_src_path)/utils/win/SkWGL_win.cpp',
 
     #testing
     '<(skia_src_path)/fonts/SkGScalerContext.cpp',
     '<(skia_src_path)/fonts/SkGScalerContext.h',
   ],
 }