Revert "Revert "speed up A8 by creating a new entry-point in SkDraw that blits the path's coverage …

include/core/SkDraw.h

Index: include/core/SkDraw.h
diff --git a/include/core/SkDraw.h b/include/core/SkDraw.h
index 772e11e00d7a4de2e1cca94e6a75856051835abb..91830946791823b66736e99b8000176314e045ca 100644
--- a/include/core/SkDraw.h
+++ b/include/core/SkDraw.h
@@ -43,8 +43,15 @@ public:
      *  affect the geometry/rasterization, then the pre matrix can just be
      *  pre-concated with the current matrix.
      */
-    void    drawPath(const SkPath& srcPath, const SkPaint&,
-                     const SkMatrix* prePathMatrix, bool pathIsMutable) const;
+    void    drawPath(const SkPath& path, const SkPaint& paint,
+                     const SkMatrix* prePathMatrix, bool pathIsMutable) const {
+        this->drawPath(path, paint, prePathMatrix, pathIsMutable, false);
+    }
+
+    void drawPath(const SkPath& path, const SkPaint& paint) const {
+        this->drawPath(path, paint, NULL, false, false);
+    }
+
     void    drawBitmap(const SkBitmap&, const SkMatrix&, const SkPaint&) const;
     void    drawSprite(const SkBitmap&, int x, int y, const SkPaint&) const;
     void    drawText(const char text[], size_t byteLength, SkScalar x,
@@ -65,8 +72,14 @@ public:
                          const uint16_t indices[], int ptCount,
                          const SkPaint& paint) const;
 
-    void drawPath(const SkPath& src, const SkPaint& paint) const {
-        this->drawPath(src, paint, NULL, false);
+    /**
+     *  Overwrite the target with the path's coverage (i.e. its mask).
+     *  Will overwrite the entire device, so it need not be zero'd first.
+     *
+     *  Only device A8 is supported right now.
+     */
+    void drawPathCoverage(const SkPath& src, const SkPaint& paint) const {
+        this->drawPath(src, paint, NULL, false, true);
     }
 
     /** Helper function that creates a mask from a path and an optional maskfilter.
@@ -107,6 +120,9 @@ private:
     void    drawDevMask(const SkMask& mask, const SkPaint&) const;
     void    drawBitmapAsMask(const SkBitmap&, const SkPaint&) const;
 
+    void    drawPath(const SkPath&, const SkPaint&, const SkMatrix* preMatrix,
+                     bool pathIsMutable, bool drawCoverage) const;
+
     /**
      *  Return the current clip bounds, in local coordinates, with slop to account
      *  for antialiasing or hairlines (i.e. device-bounds outset by 1, and then