update callsites for Make image factories

gm/multipicturedraw.cpp

Index: gm/multipicturedraw.cpp
diff --git a/gm/multipicturedraw.cpp b/gm/multipicturedraw.cpp
index 88d6cd798f931ab0bdb0fbc9f5656f182bc9d37c..c3f6b892bf71d3a24b5b75eeebadb0a291c77df9 100644
--- a/gm/multipicturedraw.cpp
+++ b/gm/multipicturedraw.cpp
@@ -511,9 +511,8 @@ namespace skiagm {
             for (int i = 0; i < composeSteps.count(); ++i) {
                 const ComposeStep& step = composeSteps[i];
 
-                SkAutoTUnref<SkImage> image(step.fSurf->newImageSnapshot());
-
-                canvas->drawImage(image, step.fX, step.fY, step.fPaint);
+                canvas->drawImage(step.fSurf->makeImageSnapshot().get(),
+                                  step.fX, step.fY, step.fPaint);
             }
         }