update callsites for Make image factories

gm/textblobmixedsizes.cpp

Index: gm/textblobmixedsizes.cpp
diff --git a/gm/textblobmixedsizes.cpp b/gm/textblobmixedsizes.cpp
index 86ab0ac8fbecb4ab4e2e3ed97a90fe93138f992a..7923489370e1789557bd1ea704ca0db11acbea2f 100644
--- a/gm/textblobmixedsizes.cpp
+++ b/gm/textblobmixedsizes.cpp
@@ -171,9 +171,7 @@ protected:
             SkAutoCanvasRestore acr(inputCanvas, true);
             // since we prepended this matrix already, we blit using identity
             inputCanvas->resetMatrix();
-            SkImage* image = surface->newImageSnapshot();
-            inputCanvas->drawImage(image, 0, 0, nullptr);
-            image->unref();
+            inputCanvas->drawImage(surface->makeImageSnapshot().get(), 0, 0, nullptr);
         }
 #endif
     }