Add new module for distance field generation.

gyp/core.gypi

 # Include this gypi to include all 'core' 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)/core/ARGB32_Clamp_Bilinear_BitmapShader.h',
@@ skipping 52 matching lines @@
         '<(skia_src_path)/core/SkCubicClipper.h',
         '<(skia_src_path)/core/SkData.cpp',
         '<(skia_src_path)/core/SkDataTable.cpp',
         '<(skia_src_path)/core/SkDebug.cpp',
         '<(skia_src_path)/core/SkDeque.cpp',
         '<(skia_src_path)/core/SkDevice.cpp',
         '<(skia_src_path)/core/SkDeviceLooper.cpp',
         '<(skia_src_path)/core/SkDeviceProfile.cpp',
         '<(skia_src_path)/lazy/SkDiscardableMemoryPool.cpp',
         '<(skia_src_path)/lazy/SkDiscardablePixelRef.cpp',
+        '<(skia_src_path)/core/SkDistanceFieldGen.cpp',
+        '<(skia_src_path)/core/SkDistanceFieldGen.h',
         '<(skia_src_path)/core/SkDither.cpp',
         '<(skia_src_path)/core/SkDraw.cpp',
         '<(skia_src_path)/core/SkDrawLooper.cpp',
         '<(skia_src_path)/core/SkDrawProcs.h',
         '<(skia_src_path)/core/SkEdgeBuilder.cpp',
         '<(skia_src_path)/core/SkEdgeClipper.cpp',
         '<(skia_src_path)/core/SkEdge.cpp',
         '<(skia_src_path)/core/SkEdge.h',
         '<(skia_src_path)/core/SkError.cpp',
         '<(skia_src_path)/core/SkErrorInternals.h',
@@ skipping 275 matching lines @@
         '<(skia_src_path)/pathops/SkPathOpsPoint.h',
         '<(skia_src_path)/pathops/SkPathOpsQuad.h',
         '<(skia_src_path)/pathops/SkPathOpsRect.h',
         '<(skia_src_path)/pathops/SkPathOpsTriangle.h',
         '<(skia_src_path)/pathops/SkPathOpsTypes.h',
         '<(skia_src_path)/pathops/SkPathWriter.h',
         '<(skia_src_path)/pathops/SkQuarticRoot.h',
         '<(skia_src_path)/pathops/SkReduceOrder.h',
     ],
 }