Simplify flattening to just write enough to call the factory

include/effects/SkTransparentShader.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 SkTransparentShader_DEFINED
 #define SkTransparentShader_DEFINED
 
@@ skipping 19 matching lines @@
 
         typedef SkShader::Context INHERITED;
     };
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTransparentShader)
 
 protected:
     virtual Context* onCreateContext(const ContextRec&, void* storage) const SK_OVERRIDE;
 
+    // we don't need to flatten anything at all
+    virtual void flatten(SkWriteBuffer&) {}
+
 private:
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
     SkTransparentShader(SkReadBuffer& buffer) : INHERITED(buffer) {}
+#endif
 
     typedef SkShader INHERITED;
 };
 
 #endif