Make GrAAConvexPathRender support paths with > 64K verts.

gm/convexpaths.cpp

Index: gm/convexpaths.cpp
diff --git a/gm/convexpaths.cpp b/gm/convexpaths.cpp
index 2c4753d95a48ff78cf7b6cc9e47058d1c31f8440..a354bd4cef3489c9419b3682bb790cb261bda75f 100644
--- a/gm/convexpaths.cpp
+++ b/gm/convexpaths.cpp
@@ -120,12 +120,30 @@ protected:
                                         20 * SK_Scalar1, 40 * SK_Scalar1,
                                         SkPath::kCCW_Direction);
 
+        // large number of points
+        enum {
+            kLength = 100,
+            kPtsPerSide = (1 << 12),
+        };
+        fPaths.push_back().moveTo(0, 0);
+        for (int i = 1; i < kPtsPerSide; ++i) { // skip the first point due to moveTo.
+            fPaths.back().lineTo(kLength * SkIntToScalar(i) / kPtsPerSide, 0);
+        }
+        for (int i = 0; i < kPtsPerSide; ++i) {
+            fPaths.back().lineTo(kLength, kLength * SkIntToScalar(i) / kPtsPerSide);
+        }
+        for (int i = kPtsPerSide; i > 0; --i) {
+            fPaths.back().lineTo(kLength * SkIntToScalar(i) / kPtsPerSide, kLength);
+        }
+        for (int i = kPtsPerSide; i > 0; --i) {
+            fPaths.back().lineTo(0, kLength * SkIntToScalar(i) / kPtsPerSide);
+        }
+
         // shallow diagonals
         fPaths.push_back().lineTo(100 * SK_Scalar1, SK_Scalar1);
         fPaths.back().lineTo(98 * SK_Scalar1, 100 * SK_Scalar1);
         fPaths.back().lineTo(3 * SK_Scalar1, 96 * SK_Scalar1);
 
-
         //It turns out arcTos are not automatically marked as convex and they
         //may in fact be ever so slightly concave.
         //fPaths.push_back().arcTo(SkRect::MakeXYWH(0, 0,