Clean up some gm factory use.

Mostly use unique_ptr more consistently.

Change-Id: I6e11b272a7904eb662dea59b03fbc309a4cfc25d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/233984
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/tools/viewer/Viewer.cpp b/tools/viewer/Viewer.cpp
index 48e9931..556c8a4 100644
--- a/tools/viewer/Viewer.cpp
+++ b/tools/viewer/Viewer.cpp
@@ -676,9 +676,9 @@
     // GMs
     int firstGM = fSlides.count();
     for (skiagm::GMFactory gmFactory : skiagm::GMRegistry::Range()) {
-        std::unique_ptr<skiagm::GM> gm(gmFactory());
+        std::unique_ptr<skiagm::GM> gm = gmFactory();
         if (!CommandLineFlags::ShouldSkip(FLAGS_match, gm->getName())) {
-            sk_sp<Slide> slide(new GMSlide(gm.release()));
+            sk_sp<Slide> slide(new GMSlide(std::move(gm)));
             fSlides.push_back(std::move(slide));
         }
     }