Add specialized sRGB blitter for SkOpts

src/opts/SkOpts_sse41.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkOpts.h"
 
 #define SK_OPTS_NS sk_sse41
 #include "SkBlurImageFilter_opts.h"
 #include "SkBlitRow_opts.h"
+#include "SkBlend_opts.h"
 
 #ifndef SK_SUPPORT_LEGACY_X86_BLITS
 
 namespace sk_sse41_new {
 
 // An SSE register holding at most 64 bits of useful data in the low lanes.
 struct m64i {
     __m128i v;
     /*implicit*/ m64i(__m128i v) : v(v) {}
     operator __m128i() const { return v; }
@@ skipping 181 matching lines @@
                 // SrcOver blend mode, with coverage folded into source alpha.
                 __m128i sc = scale(s,c),
                         AC = inv(alphas(sc));
                 return _mm_add_epi16(sc, scale(d,AC));
             }));
             dst += dstRB / sizeof(*dst);
             cov += covRB / sizeof(*cov);
         }
     }
 }
-
 }  // namespace sk_sse41_new
 
 #endif
 
 namespace SkOpts {
     void Init_sse41() {
-        box_blur_xx = sk_sse41::box_blur_xx;
-        box_blur_xy = sk_sse41::box_blur_xy;
-        box_blur_yx = sk_sse41::box_blur_yx;
+        box_blur_xx       = sk_sse41::box_blur_xx;
+        box_blur_xy       = sk_sse41::box_blur_xy;
+        box_blur_yx       = sk_sse41::box_blur_yx;
+        srcover_srgb_srgb = sk_sse41::srcover_srgb_srgb;
 
     #ifndef SK_SUPPORT_LEGACY_X86_BLITS
         blit_row_color32 = sk_sse41_new::blit_row_color32;
         blit_mask_d32_a8 = sk_sse41_new::blit_mask_d32_a8;
     #endif
         blit_row_s32a_opaque = sk_sse41::blit_row_s32a_opaque;
     }
 }