partial switch over to sp usage of shaders

src/utils/SkLua.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkLua.h"
 
 #if SK_SUPPORT_GPU
@@ skipping 64 matching lines @@
     lua_setmetatable(L, -2);
 }
 
 template <typename T> T* push_ref(lua_State* L, T* ref) {
     *(T**)lua_newuserdata(L, sizeof(T*)) = SkSafeRef(ref);
     luaL_getmetatable(L, get_mtname<T>());
     lua_setmetatable(L, -2);
     return ref;
 }
 
+template <typename T> void push_ref(lua_State* L, sk_sp<T> sp) {
+    *(T**)lua_newuserdata(L, sizeof(T*)) = sp.release();
+    luaL_getmetatable(L, get_mtname<T>());
+    lua_setmetatable(L, -2);
+}
+
 template <typename T> T* get_ref(lua_State* L, int index) {
     return *(T**)luaL_checkudata(L, index, get_mtname<T>());
 }
 
 template <typename T> T* get_obj(lua_State* L, int index) {
     return (T*)luaL_checkudata(L, index, get_mtname<T>());
 }
 
 static bool lua2bool(lua_State* L, int index) {
     return !!lua_toboolean(L, index);
@@ skipping 1875 matching lines @@
 static int lsk_newLinearGradient(lua_State* L) {
     SkScalar x0 = lua2scalar_def(L, 1, 0);
     SkScalar y0 = lua2scalar_def(L, 2, 0);
     SkColor  c0 = lua2color(L, 3);
     SkScalar x1 = lua2scalar_def(L, 4, 0);
     SkScalar y1 = lua2scalar_def(L, 5, 0);
     SkColor  c1 = lua2color(L, 6);
 
     SkPoint pts[] = { { x0, y0 }, { x1, y1 } };
     SkColor colors[] = { c0, c1 };
-    SkShader* s = SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
-    if (nullptr == s) {
+    auto s = SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
+    if (!s) {
         lua_pushnil(L);
     } else {
-        push_ref(L, s)->unref();
+        push_ref(L, std::move(s));
     }
     return 1;
 }
 
 static int lsk_newMatrix(lua_State* L) {
     push_new<SkMatrix>(L)->reset();
     return 1;
 }
 
 static int lsk_newPaint(lua_State* L) {
@@ skipping 136 matching lines @@
     REG_CLASS(L, SkTextBlob);
     REG_CLASS(L, SkTypeface);
     REG_CLASS(L, SkXfermode);
 }
 
 extern "C" int luaopen_skia(lua_State* L);
 extern "C" int luaopen_skia(lua_State* L) {
     SkLua::Load(L);
     return 0;
 }