ARM Skia NEON patches - 03 - Duplicate code removal

src/core/SkBlitMask_D32.cpp

 #include "SkBlitMask.h"
 #include "SkColor.h"
 #include "SkColorPriv.h"
 
 static void D32_A8_Color(void* SK_RESTRICT dst, size_t dstRB,
                          const void* SK_RESTRICT maskPtr, size_t maskRB,
                          SkColor color, int width, int height) {
     SkPMColor pmc = SkPreMultiplyColor(color);
     size_t dstOffset = dstRB - (width << 2);
     size_t maskOffset = maskRB - width;
@@ skipping 365 matching lines @@
 #endif
         }
     }
 }
 
 static int upscale31To255(int value) {
     value = (value << 3) | (value >> 2);
     return value;
 }
 
-static int mul(int a, int b) {
-    return a * b >> 8;
-}
-
 static int src_alpha_blend(int src, int dst, int srcA, int mask) {
 
-    return dst + mul(src - mul(srcA, dst), mask);
+    return dst + SkAlphaMul(src - SkAlphaMul(srcA, dst), mask);
 }
 
 static void LCD16_RowProc_Blend(SkPMColor* SK_RESTRICT dst,
                                 const uint16_t* SK_RESTRICT mask,
                                 const SkPMColor* SK_RESTRICT src, int count) {
     for (int i = 0; i < count; ++i) {
         uint16_t m = mask[i];
         if (0 == m) {
             continue;
         }
@@ skipping 184 matching lines @@
             if (flags & kSrcIsOpaque_RowFlag) {
                 index |= 1;
             }
             SkASSERT((size_t)index < SK_ARRAY_COUNT(gProcs));
             return gProcs[index];
         default:
             break;
     }
     return NULL;
 }