add virtual ~Effect()

include/core/SkRefCnt.h

Index: include/core/SkRefCnt.h
diff --git a/include/core/SkRefCnt.h b/include/core/SkRefCnt.h
index d33117751e0717943ec28b890bd645e98ff8f6bc..f899d1eb98e1462dae0fb115af200ecdf7e5cd5d 100644
--- a/include/core/SkRefCnt.h
+++ b/include/core/SkRefCnt.h
@@ -244,6 +244,10 @@ public:
     sk_sp() : fPtr(nullptr) {}
     sk_sp(std::nullptr_t) : fPtr(nullptr) {}
 
+    // TODO: for all these constructors and assignments that take <typename U>,
+    // can we add static assertions that sk_sp<T> -> sk_sp<U> doesn't slice
+    // (something like, T has a trivial destructor or U's destructor is virtual)?
+

[bungeman-skia, 2016/03/07 19:29:45]

Putting this here is a bit over constrained. sk_sp doesn't call 'delete', it
calls 'unref'. It sounds a bit dumb, but 'unref' in the base class could figure
out what derived class it was, downcast, and then properly delete. I think it
really is up to the individual class implementation to make sure that it's
properly written in this regard.

[mtklein_C, 2016/03/07 19:40:46]

Agreed.  Now gone.

     /**
      *  Shares the underlying object by calling ref(), so that both the argument and the newly
      *  created sk_sp both have a reference to it.