add runtime option to provide data->imagegenerator factory

tools/LazyDecodeBitmap.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "LazyDecodeBitmap.h"
 
 #include "SkData.h"
@@ skipping 10 matching lines @@
             "implementation.");
 
 //  Fits SkPicture::InstallPixelRefProc call signature.
 //  Used in SkPictureData::CreateFromStream
 bool sk_tools::LazyDecodeBitmap(const void* src, size_t length, SkBitmap* dst) {
     SkAutoDataUnref data(SkData::NewWithCopy(src, length));
     if (NULL == data.get()) {
         return false;
     }
 
-    SkAutoTDelete<SkImageGenerator> gen(SkImageGenerator::NewFromData(data));
+    SkAutoTDelete<SkImageGenerator> gen(SkImageGenerator::NewFromEncoded(data));
     if (NULL == gen.get()) {
         return false;
     }
     const SkImageInfo info = gen->getInfo();
     SkDiscardableMemory::Factory* pool = NULL;
     if ((!FLAGS_useVolatileCache) || (info.width() * info.height() < 32 * 1024)) {
         // how to do switching with SkDiscardableMemory.
         pool = SkGetGlobalDiscardableMemoryPool();
         // Only meaningful if platform has a default discardable
         // memory implementation that differs from the global DM pool.
     }
     return SkInstallDiscardablePixelRef(gen.detach(), NULL, dst, pool);
 }