Simplify flattening to just write enough to call the factory

include/core/SkXfermode.h

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkXfermode_DEFINED
@@ skipping 199 matching lines @@
                                    Coeff* src,
                                    Coeff* dst,
                                    GrTexture* background = NULL);
 
     SK_TO_STRING_PUREVIRT()
     SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
     SK_DEFINE_FLATTENABLE_TYPE(SkXfermode)
 
 protected:
     SkXfermode() {}
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
     explicit SkXfermode(SkReadBuffer& rb) : SkFlattenable(rb) {}
+#endif
 
     /** The default implementation of xfer32/xfer16/xferA8 in turn call this
         method, 1 color at a time (upscaled to a SkPMColor). The default
         implmentation of this method just returns dst. If performance is
         important, your subclass should override xfer32/xfer16/xferA8 directly.
 
         This method will not be called directly by the client, so it need not
         be implemented if your subclass has overridden xfer32/xfer16/xferA8
     */
     virtual SkPMColor xferColor(SkPMColor src, SkPMColor dst) const;
 
 private:
     enum {
         kModeCount = kLastMode + 1
     };
 
     typedef SkFlattenable INHERITED;
 };
 
 #endif