New option for arithmetic mode

gyp/effects.gypi

 # Include this gypi to include all 'effects' files
 # The parent gyp/gypi file must define:
 #       'skia_src_path'     e.g. skia/trunk/src
 #       'skia_include_path' e.g. skia/trunk/include
 #
 # The skia build defines these in common_variables.gypi.
 #
 {
   'sources': [
     '<(skia_src_path)/effects/Sk1DPathEffect.cpp',
@@ skipping 41 matching lines @@
     '<(skia_src_path)/effects/SkPixelXorXfermode.cpp',
     '<(skia_src_path)/effects/SkPorterDuff.cpp',
     '<(skia_src_path)/effects/SkRectShaderImageFilter.cpp',
     '<(skia_src_path)/effects/SkResizeImageFilter.cpp',
     '<(skia_src_path)/effects/SkStippleMaskFilter.cpp',
     '<(skia_src_path)/effects/SkTableColorFilter.cpp',
     '<(skia_src_path)/effects/SkTableMaskFilter.cpp',
     '<(skia_src_path)/effects/SkTestImageFilters.cpp',
     '<(skia_src_path)/effects/SkTileImageFilter.cpp',
     '<(skia_src_path)/effects/SkTransparentShader.cpp',
+    '<(skia_src_path)/effects/SkValidateImageFilter.cpp',
     '<(skia_src_path)/effects/SkXfermodeImageFilter.cpp',
 
     '<(skia_src_path)/effects/gradients/SkBitmapCache.cpp',
     '<(skia_src_path)/effects/gradients/SkBitmapCache.h',
     '<(skia_src_path)/effects/gradients/SkClampRange.cpp',
     '<(skia_src_path)/effects/gradients/SkClampRange.h',
     '<(skia_src_path)/effects/gradients/SkRadialGradient_Table.h',
     '<(skia_src_path)/effects/gradients/SkGradientShader.cpp',
     '<(skia_src_path)/effects/gradients/SkGradientShaderPriv.h',
     '<(skia_src_path)/effects/gradients/SkLinearGradient.cpp',
@@ skipping 40 matching lines @@
     '<(skia_include_path)/effects/SkPerlinNoiseShader.h',
     '<(skia_include_path)/effects/SkPixelXorXfermode.h',
     '<(skia_include_path)/effects/SkPorterDuff.h',
     '<(skia_include_path)/effects/SkRectShaderImageFilter.h',
     '<(skia_include_path)/effects/SkStippleMaskFilter.h',
     '<(skia_include_path)/effects/SkTableColorFilter.h',
     '<(skia_include_path)/effects/SkTableMaskFilter.h',
     '<(skia_include_path)/effects/SkTileImageFilter.h',
     '<(skia_include_path)/effects/SkTransparentShader.h',
     '<(skia_include_path)/effects/SkMagnifierImageFilter.h',
+    '<(skia_include_path)/effects/SkValidateImageFilter.h',
   ],
 }