Fix two gross memory leaks. I was neglecting to clear the SEdgeList

that I created in SPolygon::SelfIntersecting, and while
triangulating a polygon I would free the SContour, but not the
list of points associated with the contour.

[git-p4: depot-paths = "//depot/solvespace/": change = 2047]

polygon.cpp

@@ -562,12 +562,17 @@ bool SPolygon::SelfIntersecting(Vector *intersectsAt) {
     ZERO(&el);
     MakeEdgesInto(&el);
 
+    bool ret = false;
     SEdge *se;
     for(se = el.l.First(); se; se = el.l.NextAfter(se)) {
         int inters = el.AnyEdgeCrossings(se->a, se->b, intersectsAt);
-        if(inters != 1) return true;
+        if(inters != 1) {
+            ret = true;
+            break;
+        }
     }
-    return false;
+    el.Clear();
+    return ret;
 }
 
 static int TriMode, TriVertexCount;

srf/triangulate.cpp

@@ -89,6 +89,13 @@ void SPolygon::UvTriangulateInto(SMesh *m, SSurface *srf) {
         el.Clear();
         vl.Clear();
 
+        // Careful, need to free the points within the contours, and not just
+        // the contours themselves. This was a tricky memory leak.
+        for(sc = l.First(); sc; sc = l.NextAfter(sc)) {
+            if(sc->tag) {
+                sc->l.Clear();
+            }
+        }
         l.RemoveTagged();
     }
 }