return pictures as sk_sp

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1811703002

Review URL: https://codereview.chromium.org/1811703002
diff --git a/tools/get_images_from_skps.cpp b/tools/get_images_from_skps.cpp
index 7d0854d..e6bb6e2 100644
--- a/tools/get_images_from_skps.cpp
+++ b/tools/get_images_from_skps.cpp
@@ -90,7 +90,7 @@
     for (SkString file; iter.next(&file); ) {
         SkAutoTDelete<SkStream> stream =
                 SkStream::NewFromFile(SkOSPath::Join(inputs, file.c_str()).c_str());
-        SkAutoTUnref<SkPicture> picture(SkPicture::CreateFromStream(stream));
+        sk_sp<SkPicture> picture(SkPicture::MakeFromStream(stream));
 
         SkDynamicMemoryWStream scratch;
         Sniffer sniff;