Refactor to put SkXfermode_opts inside SK_OPTS_NS.

src/opts/SkNx_neon.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 SkNx_neon_DEFINED
 #define SkNx_neon_DEFINED
 
-namespace {  // See SkNx.h
-
 // Well, this is absurd.  The shifts require compile-time constant arguments.
 
 #define SHIFT8(op, v, bits) switch(bits) { \
     case  1: return op(v,  1);  case  2: return op(v,  2);  case  3: return op(v,  3); \
     case  4: return op(v,  4);  case  5: return op(v,  5);  case  6: return op(v,  6); \
     case  7: return op(v,  7); \
     } return fVec
 
 #define SHIFT16(op, v, bits) if (bits < 8) { SHIFT8(op, v, bits); } switch(bits) { \
                                 case  8: return op(v,  8);  case  9: return op(v,  9); \
@@ skipping 353 matching lines @@
         return vbslq_u8(fVec, t.fVec, e.fVec);
     }
 
     uint8x16_t fVec;
 };
 
 #undef SHIFT32
 #undef SHIFT16
 #undef SHIFT8
 
-}  // namespace
-
 #endif//SkNx_neon_DEFINED