add ImageGenerator::NewFromData to porting layer

tests/PDFJpegEmbedTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkDocument.h"
 #include "SkCanvas.h"
 #include "SkImageGenerator.h"
 #include "SkData.h"
 #include "SkStream.h"
-#include "SkDecodingImageGenerator.h"
 
 #include "Resources.h"
 #include "Test.h"
 
 // Returned bitmap is lazy.  Only lazy bitmaps hold onto the original data.
 static SkBitmap bitmap_from_data(SkData* data) {
     SkASSERT(data);
     SkBitmap bm;
-    SkInstallDiscardablePixelRef(
-            SkDecodingImageGenerator::Create(
-                    data, SkDecodingImageGenerator::Options()), &bm);
+    SkInstallDiscardablePixelRef(data, &bm);
     return bm;
 }
 
 static bool is_subset_of(SkData* smaller, SkData* larger) {
     SkASSERT(smaller && larger);
     if (smaller->size() > larger->size()) {
         return false;
     }
     size_t size = smaller->size();
     size_t size_diff = larger->size() - size;
@@ skipping 58 matching lines @@
 
     // The following is for debugging purposes only.
     const char* outputPath = getenv("SKIA_TESTS_PDF_JPEG_EMBED_OUTPUT_PATH");
     if (outputPath) {
         SkFILEWStream output(outputPath);
         if (output.isValid()) {
             output.write(pdfData->data(), pdfData->size());
         }
     }
 }