Propagate validation errors

src/core/SkPicture.cpp

Index: src/core/SkPicture.cpp
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index 5409eb34651947441c7353c82e3bfab26b4047b4..60987b64c0a887c19c44588cd3df106e8a195cf5 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -157,7 +157,7 @@ bool SkPicture::InternalOnly_BufferIsSKP(SkReadBuffer* buffer, SkPictInfo* pInfo
 
 sk_sp<SkPicture> SkPicture::Forwardport(const SkPictInfo& info,
                                         const SkPictureData* data,
-                                        const SkReadBuffer* buffer) {
+                                        SkReadBuffer* buffer) {
     if (!data) {
         return nullptr;
     }