Revert of Make SkPicture/SkImageGenerator default to SkCodec

tests/KtxTest.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 "Resources.h"
 #include "SkBitmap.h"
 #include "SkData.h"
@@ skipping 125 matching lines @@
     uint8_t *row = decodedPixels;
     for (int j = 0; j < decodedBitmap.height(); ++j) {
         for (int i = 0; i < decodedBitmap.width(); ++i) {
             SkPMColor pixel = *(reinterpret_cast<SkPMColor*>(row + i*sizeof(SkPMColor)));
             REPORTER_ASSERT(reporter, SkPreMultiplyARGB(0x80, 0xFF, 0xFF, 0xFF) == pixel);
         }
         row += decodedBitmap.rowBytes();
     }
 }
 
-// For KtxReexportPKM, below. Defined in SkImageDecoder_ktx.cpp
-extern SkImageGenerator* decoder_image_generator(SkData*);
-
 /**
  * Finally, make sure that if we get ETC1 data from a PKM file that we can then
  * accurately write it out into a KTX file (i.e. transferring the ETC1 data from
  * the PKM to the KTX should produce an identical KTX to the one we have on file)
  */
 DEF_TEST(KtxReexportPKM, reporter) {
     SkString pkmFilename = GetResourcePath("mandrill_128.pkm");
 
     // Load PKM file into a bitmap
     SkBitmap etcBitmap;
     SkAutoTUnref<SkData> fileData(SkData::NewFromFileName(pkmFilename.c_str()));
     if (nullptr == fileData) {
         SkDebugf("KtxReexportPKM: can't load test file %s\n", pkmFilename.c_str());
         return;
     }
 
     bool installDiscardablePixelRefSuccess =
-        SkDEPRECATED_InstallDiscardablePixelRef(decoder_image_generator(fileData), &etcBitmap);
+        SkDEPRECATED_InstallDiscardablePixelRef(fileData, &etcBitmap);
     if (!installDiscardablePixelRefSuccess) {
         ERRORF(reporter, "failed to create discardable pixelRef from KTX file");
         return;
     }
 
     // Write the bitmap out to a KTX file.
     SkData *ktxDataPtr = SkImageEncoder::EncodeData(etcBitmap, SkImageEncoder::kKTX_Type, 0);
     SkAutoDataUnref newKtxData(ktxDataPtr);
     REPORTER_ASSERT(reporter, ktxDataPtr);
 
     // See is this data is identical to data in existing ktx file.
     SkString ktxFilename = GetResourcePath("mandrill_128.ktx");
     SkAutoDataUnref oldKtxData(SkData::NewFromFileName(ktxFilename.c_str()));
     REPORTER_ASSERT(reporter, oldKtxData->equals(newKtxData));
 }