guarded change to SkImageGenerator to make getInfo() const

include/codec/SkCodec.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCodec_DEFINED
 #define SkCodec_DEFINED
 
@@ skipping 40 matching lines @@
     }
 
 protected:
     SkCodec(const SkImageInfo&, SkStream*);
 
     /**
      *  The SkAlphaType is a conservative answer. i.e. it is possible that it
      *  initially returns a non-opaque answer, but completing the decode
      *  reveals that the image is actually opaque.
      */
+#ifdef SK_SUPPORT_LEGACY_BOOL_ONGETINFO
     bool onGetInfo(SkImageInfo* info) SK_OVERRIDE {
         *info = fInfo;
         return true;
     }
+#endif
 
     // Helper for subclasses.
     const SkImageInfo& getOriginalInfo() { return fInfo; }
 
     virtual SkISize onGetScaledDimensions(float /* desiredScale */) const {
         // By default, scaling is not supported.
         return fInfo.dimensions();
     }
 
     /**
@@ skipping 17 matching lines @@
      *
      */
     SkStream* stream() {
         return fStream.get();
     }
 
 private:
     const SkImageInfo       fInfo;
     SkAutoTDelete<SkStream> fStream;
     bool                    fNeedsRewind;
+
+    typedef SkImageGenerator INHERITED;
 };
 #endif // SkCodec_DEFINED