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

src/core/SkScan.h

Index: src/core/SkScan.h
diff --git a/src/core/SkScan.h b/src/core/SkScan.h
index 46a81073ead2ff09345ffd05318c2aeb046c2051..96c58c5f370962f21b31f7932d34677c3a88ff4a 100644
--- a/src/core/SkScan.h
+++ b/src/core/SkScan.h
@@ -41,10 +41,8 @@ public:
     static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
                               const SkRasterClip&, SkBlitter*);
     static void FillTriangle(const SkPoint pts[], const SkRasterClip&, SkBlitter*);
-    static void HairLine(const SkPoint&, const SkPoint&, const SkRasterClip&,
-                         SkBlitter*);
-    static void AntiHairLine(const SkPoint&, const SkPoint&, const SkRasterClip&,
-                             SkBlitter*);
+    static void HairLine(SkPoint, SkPoint, const SkRasterClip&, SkBlitter*);
+    static void AntiHairLine(SkPoint, SkPoint, const SkRasterClip&, SkBlitter*);
     static void HairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
     static void AntiHairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
     static void HairPath(const SkPath&, const SkRasterClip&, SkBlitter*);
@@ -66,10 +64,8 @@ private:
 
     static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
                               const SkRegion*, SkBlitter*);
-    static void HairLineRgn(const SkPoint&, const SkPoint&, const SkRegion*,
-                         SkBlitter*);
-    static void AntiHairLineRgn(const SkPoint&, const SkPoint&, const SkRegion*,
-                             SkBlitter*);
+    static void HairLineRgn(SkPoint, SkPoint, const SkRegion*, SkBlitter*);
+    static void AntiHairLineRgn(SkPoint, SkPoint, const SkRegion*, SkBlitter*);
 };
 
 /** Assign an SkXRect from a SkIRect, by promoting the src rect's coordinates