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/fm/fm.cpp b/tools/fm/fm.cpp
index ee6c282..f2a73f4 100644
--- a/tools/fm/fm.cpp
+++ b/tools/fm/fm.cpp
@@ -381,7 +381,7 @@
         if (skiagm::GMFactory* factory = gm_factories.find(name)) {
             std::shared_ptr<skiagm::GM> gm{(*factory)()};
             source->name = name;
-            init(source, gm);
+            init(source, std::move(gm));
             continue;
         }