fixes wacky build on android. no other explanation received

git-svn-id: http://skia.googlecode.com/svn/trunk@315 2bbb7eff-a529-9590-31e7-b0007b416f81

src/core/SkPictureFlat.h

@@ -71,6 +71,8 @@ protected:
 
 class SkTypefacePlayback : public SkRefCntPlayback {
 public:
+    virtual ~SkTypefacePlayback() {}
+
     virtual void setupBuffer(SkFlattenableReadBuffer& buffer) const {
         buffer.setTypefaceArray((SkTypeface**)fArray, fCount);
     }