change hairline procs to take SkPoint by value, more efficient on SSE and NEON

src/core/SkDraw.cpp

Index: src/core/SkDraw.cpp
diff --git a/src/core/SkDraw.cpp b/src/core/SkDraw.cpp
index c4c1bc5ddd4db2fbd216c92f5f7b8aff9d22960c..636eaa6f61950ec35b5132798c6043c18d8774d4 100644
--- a/src/core/SkDraw.cpp
+++ b/src/core/SkDraw.cpp
@@ -1876,8 +1876,7 @@ void SkDraw::drawPosText(const char text[], size_t byteLength,
 
 ///////////////////////////////////////////////////////////////////////////////
 
-typedef void (*HairProc)(const SkPoint&, const SkPoint&, const SkRasterClip&,
-                         SkBlitter*);
+typedef void (*HairProc)(SkPoint, SkPoint, const SkRasterClip&, SkBlitter*);
 
 static HairProc ChooseHairProc(bool doAntiAlias) {
     return doAntiAlias ? SkScan::AntiHairLine : SkScan::HairLine;