Change SkDecodingImageGenerator API

src/lazy/SkDiscardablePixelRef.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 "SkDiscardablePixelRef.h"
 #include "SkDiscardableMemory.h"
 #include "SkImageGenerator.h"
@@ skipping 54 matching lines @@
     return pixels;
 }
 void SkDiscardablePixelRef::onUnlockPixels() {
     fDiscardableMemory->unlock();
 }
 
 bool SkInstallDiscardablePixelRef(SkImageGenerator* generator,
                                   SkBitmap* dst,
                                   SkDiscardableMemory::Factory* factory) {
     SkImageInfo info;
-    SkASSERT(generator != NULL);
-    if ((NULL == generator)
-        || (!generator->getInfo(&info))
+    SkAutoTDelete<SkImageGenerator> autoGenerator(generator);
+    if ((NULL == autoGenerator.get())
+        || (!autoGenerator->getInfo(&info))
         || (!dst->setConfig(info, 0))) {
-        SkDELETE(generator);
         return false;
     }
     SkASSERT(dst->config() != SkBitmap::kNo_Config);
-    if (dst->empty()) { // Use a normal pixelref.
-        SkDELETE(generator);  // Do not need this anymore.
+    if (dst->empty()) {  // Use a normal pixelref.
         return dst->allocPixels(NULL, NULL);
     }
-    SkAutoTUnref<SkDiscardablePixelRef> ref(SkNEW_ARGS(SkDiscardablePixelRef,
-                               (info, generator, dst->rowBytes(), factory)));
+    SkAutoTUnref<SkDiscardablePixelRef> ref(
+        SkNEW_ARGS(SkDiscardablePixelRef,
+                   (info, autoGenerator.detach(), dst->rowBytes(), factory)));
     dst->setPixelRef(ref);
     return true;
 }