switch surface to sk_sp

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1817383002
CQ_EXTRA_TRYBOTS=client.skia.compile:Build-Ubuntu-GCC-x86_64-Release-CMake-Trybot,Build-Mac-Clang-x86_64-Release-CMake-Trybot

Review URL: https://codereview.chromium.org/1817383002
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index 2718ee9..459402b 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -791,7 +791,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-SkSurface* SkPictureRecord::onNewSurface(const SkImageInfo& info, const SkSurfaceProps&) {
+sk_sp<SkSurface> SkPictureRecord::onNewSurface(const SkImageInfo& info, const SkSurfaceProps&) {
     return nullptr;
 }