move setshader to sk_sp

tools/debugger/SkDrawCommand.cpp

Index: tools/debugger/SkDrawCommand.cpp
diff --git a/tools/debugger/SkDrawCommand.cpp b/tools/debugger/SkDrawCommand.cpp
index 5dc6079897c21bc6807c7181404650f1af72fb7b..af1270c9e5903272803fb874bab65ab82e5ed147 100644
--- a/tools/debugger/SkDrawCommand.cpp
+++ b/tools/debugger/SkDrawCommand.cpp
@@ -1125,8 +1125,7 @@ static void extract_json_paint_shader(Json::Value& jsonPaint, UrlDataManager& ur
         Json::Value jsonShader = jsonPaint[SKDEBUGCANVAS_ATTRIBUTE_SHADER];
         SkShader* shader = (SkShader*) load_flattenable(jsonShader, urlDataManager);
         if (shader != nullptr) {
-            target->setShader(shader);
-            shader->unref();
+            target->setShader(sk_ref_sp(shader));
         }
     }
 }