Revert of Generate Signed Distance Field directly from vector path

gn/gpu.gni

 # Copyright 2016 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Things are easiest for everyone if these source paths are absolute.
 _src = get_path_info("../src", "abspath")
 _include = get_path_info("../include", "abspath")
 
 skia_gpu_sources = [
@@ skipping 74 matching lines @@
   "$_src/gpu/GrBufferAllocPool.h",
   "$_src/gpu/GrCaps.cpp",
   "$_src/gpu/GrClipStackClip.h",
   "$_src/gpu/GrClipStackClip.cpp",
   "$_src/gpu/GrColorSpaceXform.cpp",
   "$_src/gpu/GrContext.cpp",
   "$_src/gpu/GrContextPriv.h",
   "$_src/gpu/GrCoordTransform.cpp",
   "$_src/gpu/GrDefaultGeoProcFactory.cpp",
   "$_src/gpu/GrDefaultGeoProcFactory.h",
-  "$_src/gpu/GrDistanceFieldGenFromVector.cpp",
-  "$_src/gpu/GrDistanceFieldGenFromVector.h",
   "$_src/gpu/GrDrawingManager.cpp",
   "$_src/gpu/GrDrawingManager.h",
   "$_src/gpu/GrDrawOpAtlas.cpp",
   "$_src/gpu/GrDrawOpAtlas.h",
   "$_src/gpu/GrFixedClip.cpp",
   "$_src/gpu/GrFixedClip.h",
   "$_src/gpu/GrFragmentProcessor.cpp",
   "$_src/gpu/GrGeometryProcessor.h",
   "$_src/gpu/GrGlyph.h",
   "$_src/gpu/GrGpu.cpp",
@@ skipping 439 matching lines @@
 
 skia_native_gpu_sources = [
   "$_src/gpu/gl/GrGLDefaultInterface_native.cpp",
   "$_src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp",
   "$_src/gpu/gl/win/GrGLCreateNativeInterface_win.cpp",
   "$_src/gpu/gl/glx/GrGLCreateNativeInterface_glx.cpp",
   "$_src/gpu/gl/egl/GrGLCreateNativeInterface_egl.cpp",
   "$_src/gpu/gl/iOS/GrGLCreateNativeInterface_iOS.cpp",
   "$_src/gpu/gl/android/GrGLCreateNativeInterface_android.cpp",
 ]