Refactor to put SkXfermode_opts inside SK_OPTS_NS.

src/opts/SkXfermode_opts.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef Sk4pxXfermode_DEFINED
 #define Sk4pxXfermode_DEFINED
 
 #include "Sk4px.h"
 #include "SkPMFloat.h"
 #include "SkXfermode_proccoeff.h"
 
-namespace /* TODO: SK_OPTS_NS */ {
+namespace SK_OPTS_NS {
 
 // Most xfermodes can be done most efficiently 4 pixels at a time in 8 or 16-bit fixed point.
 #define XFERMODE(Name) static Sk4px SK_VECTORCALL Name(Sk4px s, Sk4px d)
 
 XFERMODE(Clear) { return Sk4px::DupPMColor(0); }
 XFERMODE(Src)   { return s; }
 XFERMODE(Dst)   { return d; }
 XFERMODE(SrcIn)   { return     s.approxMulDiv255(d.alphas()      ); }
 XFERMODE(SrcOut)  { return     s.approxMulDiv255(d.alphas().inv()); }
 XFERMODE(SrcOver) { return s + d.approxMulDiv255(s.alphas().inv()); }
@@ skipping 241 matching lines @@
         // We do aa in full float precision before going back down to bytes, because we can!
         SkPMFloat a = Sk4f(aa) * Sk4f(1.0f/255);
         b = b*a + d*(Sk4f(1)-a);
         return b.round();
     }
 
     ProcF fProcF;
     typedef SkProcCoeffXfermode INHERITED;
 };
 
-static SkXfermode* SkCreate4pxXfermode(const ProcCoeff& rec, SkXfermode::Mode mode) {
+static SkXfermode* create_xfermode(const ProcCoeff& rec, SkXfermode::Mode mode) {
     switch (mode) {
     #define CASE(Mode) case SkXfermode::k##Mode##_Mode: \
         return SkNEW_ARGS(Sk4pxXfermode, (rec, mode, &Mode, &xfer_aa<Mode>))
         CASE(Clear);
         CASE(Src);
         CASE(Dst);
         CASE(SrcOver);
         CASE(DstOver);
         CASE(SrcIn);
         CASE(DstIn);
@@ skipping 22 matching lines @@
     #undef CASE
 
         default: break;
     }
     return nullptr;
 }
 
 } // namespace SK_NS_OPTS
 
 #endif//Sk4pxXfermode_DEFINED