Add test case for Issue 2895

Author: catamorphism

src/test/run-pass/issue-2895.rs

@@ -0,0 +1,16 @@
+use sys::size_of;
+extern mod std;
+
+struct Cat {
+    x: int
+}
+
+struct Kitty {
+    x: int,
+    drop {}
+}
+
+fn main() {
+    assert (size_of::<Cat>() == 8 as uint);
+    assert (size_of::<Kitty>() == 16 as uint);
+}