make pm4f be RGBA always, not pmcolor order

src/core/SkSpanProcs.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkColorFilter.h"
 #include "SkHalf.h"
 #include "SkNx.h"
 #include "SkPaint.h"
 #include "SkPixmap.h"
 #include "SkPM4f.h"
 #include "SkPM4fPriv.h"
 #include "SkSpanProcs.h"
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 static void load_l32(const SkPixmap& src, int x, int y, SkPM4f span[], int count) {
     SkASSERT(count > 0);
     const uint32_t* addr = src.addr32(x, y);
     SkASSERT(src.addr32(x + count - 1, y));
 
     for (int i = 0; i < count; ++i) {
-        (SkNx_cast<float>(Sk4b::Load(&addr[i])) * Sk4f(1.0f/255)).store(span[i].fVec);
+        (to_4f_rgba(addr[i]) * Sk4f(1.0f/255)).store(span[i].fVec);
     }
 }
 
 static void load_s32(const SkPixmap& src, int x, int y, SkPM4f span[], int count) {
     SkASSERT(count > 0);
     const uint32_t* addr = src.addr32(x, y);
     SkASSERT(src.addr32(x + count - 1, y));
 
     for (int i = 0; i < count; ++i) {
-        srgb_to_linear(SkNx_cast<float>(Sk4b::Load(&addr[i])) * Sk4f(1.0f/255)).store(span[i].fVec);
+        srgb_to_linear(to_4f_rgba(addr[i]) * Sk4f(1.0f/255)).store(span[i].fVec);
     }
 }
 
 static void load_f16(const SkPixmap& src, int x, int y, SkPM4f span[], int count) {
     SkASSERT(count > 0);
     const uint64_t* addr = src.addr64(x, y);
     SkASSERT(src.addr64(x + count - 1, y));
 
     for (int i = 0; i < count; ++i) {
         SkHalfToFloat_01(addr[i]).store(span[i].fVec);
@@ skipping 40 matching lines @@
     paint.getColorFilter()->filterSpan4f(span, count, span);
 }
 
 SkFilterSpanProc SkFilterSpanProc_Choose(const SkPaint& paint) {
     if (paint.getColorFilter()) {
         return 0xFF == paint.getAlpha() ? colorfilter_filterspan : colorfilter_alpha_filterspan;
     } else {
         return 0xFF == paint.getAlpha() ? noop_filterspan : alpha_filterspan;
     }
 }