Bug 1364691 - don't use walk_convex_edges in Skia path rendering unless edge count is at least 2. r=mchang

MozReview-Commit-ID: 8lN0tpqZIEh

gfx/skia/skia/src/core/SkScan_AAAPath.cpp

@@ -1682,7 +1682,7 @@ static SK_ALWAYS_INLINE void aaa_fill_path(const SkPath& path, const SkIRect& cl
         rightBound = SkTMin(rightBound, SkIntToFixed(ir.fRight));
     }
 
-    if (!path.isInverseFillType() && path.isConvex()) {
+    if (!path.isInverseFillType() && path.isConvex() && count >= 2) {
         SkASSERT(count >= 2);   // convex walker does not handle missing right edges
         aaa_walk_convex_edges(&headEdge, blitter, start_y, stop_y,
                               leftBound, rightBound, isUsingMask);

gfx/skia/skia/src/core/SkScan_Path.cpp

@@ -467,7 +467,7 @@ void sk_fill_path(const SkPath& path, const SkIRect& clipRect, SkBlitter* blitte
         proc = PrePostInverseBlitterProc;
     }
 
-    if (path.isConvex() && (nullptr == proc)) {
+    if (path.isConvex() && (nullptr == proc) && count >= 2) {
         SkASSERT(count >= 2);   // convex walker does not handle missing right edges
         walk_convex_edges(&headEdge, path.getFillType(), blitter, start_y, stop_y, nullptr);
     } else {