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/pdf/SkPDFDevice.h b/src/pdf/SkPDFDevice.h
index 138ec19..cfc2b54 100644
--- a/src/pdf/SkPDFDevice.h
+++ b/src/pdf/SkPDFDevice.h
@@ -195,7 +195,7 @@
         return fLegacyBitmap;
     }
 
-    SkSurface* newSurface(const SkImageInfo&, const SkSurfaceProps&) override;
+    sk_sp<SkSurface> makeSurface(const SkImageInfo&, const SkSurfaceProps&) override;
 
     void drawAnnotation(const SkDraw&, const SkRect&, const char key[], SkData* value) override;