Add a paint filter utility canvas (SkPaintFilterCanvas)

gyp/utils.gypi

 # Include this gypi to include all 'utils' 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': [
         # Classes for a threadpool.
@@ skipping 12 matching lines @@
         '<(skia_include_path)/utils/SkDumpCanvas.h',
         '<(skia_include_path)/utils/SkEventTracer.h',
         '<(skia_include_path)/utils/SkInterpolator.h',
         '<(skia_include_path)/utils/SkLayer.h',
         '<(skia_include_path)/utils/SkMatrix44.h',
         '<(skia_include_path)/utils/SkMeshUtils.h',
         '<(skia_include_path)/utils/SkNinePatch.h',
         '<(skia_include_path)/utils/SkNoSaveLayerCanvas.h',
         '<(skia_include_path)/utils/SkNWayCanvas.h',
         '<(skia_include_path)/utils/SkNullCanvas.h',
+        '<(skia_include_path)/utils/SkPaintFilterCanvas.h',
         '<(skia_include_path)/utils/SkParse.h',
         '<(skia_include_path)/utils/SkParsePaint.h',
         '<(skia_include_path)/utils/SkParsePath.h',
         '<(skia_include_path)/utils/SkPictureUtils.h',
         '<(skia_include_path)/utils/SkRandom.h',
         '<(skia_include_path)/utils/SkRTConf.h',
         '<(skia_include_path)/utils/SkTextBox.h',
 
         '<(skia_src_path)/utils/SkBase64.cpp',
         '<(skia_src_path)/utils/SkBase64.h',
@@ skipping 20 matching lines @@
         '<(skia_src_path)/utils/SkMatrix22.cpp',
         '<(skia_src_path)/utils/SkMatrix22.h',
         '<(skia_src_path)/utils/SkMatrix44.cpp',
         '<(skia_src_path)/utils/SkMD5.cpp',
         '<(skia_src_path)/utils/SkMD5.h',
         '<(skia_src_path)/utils/SkMeshUtils.cpp',
         '<(skia_src_path)/utils/SkNinePatch.cpp',
         '<(skia_src_path)/utils/SkNWayCanvas.cpp',
         '<(skia_src_path)/utils/SkNullCanvas.cpp',
         '<(skia_src_path)/utils/SkOSFile.cpp',
+        '<(skia_src_path)/utils/SkPaintFilterCanvas.cpp',
         '<(skia_src_path)/utils/SkParse.cpp',
         '<(skia_src_path)/utils/SkParseColor.cpp',
         '<(skia_src_path)/utils/SkParsePath.cpp',
         '<(skia_src_path)/utils/SkPictureUtils.cpp',
         '<(skia_src_path)/utils/SkPatchGrid.cpp',
         '<(skia_src_path)/utils/SkPatchGrid.h',
         '<(skia_src_path)/utils/SkPatchUtils.cpp',
         '<(skia_src_path)/utils/SkPatchUtils.h',
         '<(skia_src_path)/utils/SkPathUtils.cpp',
         '<(skia_src_path)/utils/SkSHA1.cpp',
@@ skipping 42 matching lines @@
         '<(skia_src_path)/utils/win/SkWGL.h',
         '<(skia_src_path)/utils/win/SkWGL_win.cpp',
 
         #testing
         '<(skia_src_path)/fonts/SkGScalerContext.cpp',
         '<(skia_src_path)/fonts/SkGScalerContext.h',
         '<(skia_src_path)/fonts/SkTestScalerContext.cpp',
         '<(skia_src_path)/fonts/SkTestScalerContext.h',
     ],
 }