change readTypeface to return sk_sp

src/core/SkReadBuffer.cpp

Index: src/core/SkReadBuffer.cpp
diff --git a/src/core/SkReadBuffer.cpp b/src/core/SkReadBuffer.cpp
index 5356d4a6b1f47ab27db1ba9d7eb9743403e77da4..43eaf2026134c7832aa0213c50424ca5d33ff008 100644
--- a/src/core/SkReadBuffer.cpp
+++ b/src/core/SkReadBuffer.cpp
@@ -297,14 +297,13 @@ sk_sp<SkImage> SkReadBuffer::readImage() {
     return image ? image : MakeEmptyImage(width, height);
 }
 
-SkTypeface* SkReadBuffer::readTypeface() {
-
+sk_sp<SkTypeface> SkReadBuffer::readTypeface() {
     uint32_t index = fReader.readU32();
     if (0 == index || index > (unsigned)fTFCount) {
         return nullptr;
     } else {
         SkASSERT(fTFArray);
-        return fTFArray[index - 1];
+        return sk_ref_sp(fTFArray[index - 1]);
     }
 }