Re-proc SkBlitRow::Color32 for ARM.

src/opts/SkBlitRow_opts_arm_neon.cpp

Index: src/opts/SkBlitRow_opts_arm_neon.cpp
diff --git a/src/opts/SkBlitRow_opts_arm_neon.cpp b/src/opts/SkBlitRow_opts_arm_neon.cpp
index 4a6514af7f0d431f0c152b7a85c06f41c6479d61..93bd8516e31b9e89065d177ca8df248034ad0ecf 100644
--- a/src/opts/SkBlitRow_opts_arm_neon.cpp
+++ b/src/opts/SkBlitRow_opts_arm_neon.cpp
@@ -1730,3 +1730,20 @@ const SkBlitRow::Proc32 sk_blitrow_platform_32_procs_arm_neon[] = {
     NULL
 #endif
 };
+
+#include "Sk4px.h"
+
+void sk_blitrow_color32_arm_neon(SkPMColor* dst, const SkPMColor* src, int count, SkPMColor color) {
+    // Until it becomes a little more reasonable to assume we'll be built with NEON,
+    // we copy our Sk4px implementation of SkBlitRow::Color32 here so it picks up NEON at runtime.
+    unsigned invA = 255 - SkGetPackedA32(color);
+    invA += invA >> 7;
+    SkASSERT(invA < 256);  // Our caller has already handled the alpha == 0 case.
+
+    Sk16h colorHighAndRound = Sk4px(color).widenHi() + Sk16h(128);
+    Sk16b invA_16x(invA);
+
+    Sk4px::MapSrc(count, dst, src, [&](const Sk4px& src4) -> Sk4px {
+        return src4.mulWiden(invA_16x).addNarrowHi(colorHighAndRound);
+    });
+}