Ensure proper finalization of garbage-collected types.

Source/core/css/CSSBasicShapes.h

Index: Source/core/css/CSSBasicShapes.h
diff --git a/Source/core/css/CSSBasicShapes.h b/Source/core/css/CSSBasicShapes.h
index 78b84df13d793817ce10a33bcdce42719be87afb..0c557e265ea6a2d30e5192e9e573ec44f9785f02 100644
--- a/Source/core/css/CSSBasicShapes.h
+++ b/Source/core/css/CSSBasicShapes.h
@@ -60,8 +60,10 @@ public:
 
     virtual void trace(Visitor* visitor) { visitor->trace(m_layoutBox); }
 
+#if !ENABLE(OILPAN)

[haraken, 2014/03/11 10:26:37]

I'm not that happy to have a lot of ENABLE(OILPAN) flags on destructors for the
following reasons:

- It will mess up the code base.
- (If I'm understanding correctly,) if we add !ENABLE(OILPAN), compilers will
implicitly generate the destructor in the header file. This can cause #include
cycles. (That's why Blink writes empty destructors in cpp files.)

[Erik Corry, 2014/03/11 10:34:26]

This is unfortunate, but the warning from the clang plugin seems valuable.
I think this issue does not arise, because the destructors that are ifdeffed out
are only the truly trivial ones.  The classes that contain a RefPtr or an OwnPtr
in oilpan mode cannot be ifdeffed out (and the plugin will check this), and
those are the ones that would have caused problems when implicitly generated in
the header file.

 public:
     virtual ~CSSBasicShape() { }
+#endif
 
 protected:
     CSSBasicShape() { }