Add special handling of rectori case for gpu

src/effects/SkDashPathEffect.cpp

Index: src/effects/SkDashPathEffect.cpp
===================================================================
--- src/effects/SkDashPathEffect.cpp	(revision 9163)
+++ src/effects/SkDashPathEffect.cpp	(working copy)
@@ -237,6 +237,7 @@
 
     const SkScalar* intervals = fIntervals;
     SkScalar        dashCount = 0;
+    int             segCount = 0;
 
     SkPath cullPathStorage;
     const SkPath* srcPtr = &src;
@@ -291,6 +292,7 @@
             addedSegment = false;
             if (is_even(index) && dlen > 0 && !skipFirstSegment) {
                 addedSegment = true;
+                ++segCount;
 
                 if (specialLine) {
                     lineRec.addSegment(SkDoubleToScalar(distance),
@@ -322,9 +324,14 @@
         if (meas.isClosed() && is_even(fInitialDashIndex) &&
                 fInitialDashLength > 0) {
             meas.getSegment(0, SkScalarMul(fInitialDashLength, scale), dst, !addedSegment);
+            ++segCount;
         }
     } while (meas.nextContour());
 
+    if (segCount > 1) {
+        dst->setConvexity(SkPath::kConcave_Convexity);
+    }
+
     return true;
 }