update callsites for Make image factories

src/core/SkPictureImageGenerator.cpp

Index: src/core/SkPictureImageGenerator.cpp
diff --git a/src/core/SkPictureImageGenerator.cpp b/src/core/SkPictureImageGenerator.cpp
index 67834876ca4761f71fc40f63008d8d85d3537e86..f90ac0f1eea5c8072587ffcbcf4c2486810a6276 100644
--- a/src/core/SkPictureImageGenerator.cpp
+++ b/src/core/SkPictureImageGenerator.cpp
@@ -151,8 +151,8 @@ GrTexture* SkPictureImageGenerator::onGenerateTexture(GrContext* ctx, const SkIR
     }
     surface->getCanvas()->clear(0); // does NewRenderTarget promise to do this for us?
     surface->getCanvas()->drawPicture(fPicture, &matrix, fPaint.getMaybeNull());
-    SkAutoTUnref<SkImage> image(surface->newImageSnapshot());
-    if (!image.get()) {
+    sk_sp<SkImage> image(surface->makeImageSnapshot());
+    if (!image) {
         return nullptr;
     }
     return SkSafeRef(as_IB(image)->peekTexture());