Fix std.typecons.scoped problem with interface inheritance

std/typecons.d

@@ -2569,7 +2569,7 @@ private void destroy(T)(T obj) if (is(T == class))
     }
     static if (!is(T == Object) && is(T Base == super))
     {
-        Base b = obj;
+        Base[0] b = obj;
         destroy(b);
     }
 }
@@ -2618,6 +2618,27 @@ unittest
     assert(A.dead, "asdasd");
 }
 
+unittest
+{
+    static class A {
+    static int sdtor;
+
+    this() { ++sdtor; assert(sdtor == 1); }
+    ~this() { assert(sdtor == 1); --sdtor; }
+    }
+
+    interface Bob {}
+
+    static class ABob : A, Bob {
+    this() { ++sdtor; assert(sdtor == 2); }
+    ~this() { assert(sdtor == 2); --sdtor; }
+    }
+
+    A.sdtor = 0;
+    scope(exit) assert(A.sdtor == 0);
+    auto abob = scoped!ABob();
+}
+
 /**
 Defines a simple, self-documenting yes/no flag. This makes it easy for
 APIs to define functions accepting flags without resorting to $(D