diff --git a/src/core/SkDescriptor.cpp b/src/core/SkDescriptor.cpp
index 4c64753f75..9ffce8999c 100644
--- a/src/core/SkDescriptor.cpp
+++ b/src/core/SkDescriptor.cpp
@@ -29,8 +29,8 @@ void* SkDescriptor::operator new(size_t) {
     SK_ABORT("Descriptors are created with placement new.");
 }
 
-void SkDescriptor::flatten(SkWriteBuffer& buffer) {
-    buffer.writePad32(static_cast<void*>(this), this->fLength);
+void SkDescriptor::flatten(SkWriteBuffer& buffer) const {
+    buffer.writePad32(static_cast<const void*>(this), this->fLength);
 }
 
 void* SkDescriptor::addEntry(uint32_t tag, size_t length, const void* data) {
diff --git a/src/core/SkDescriptor.h b/src/core/SkDescriptor.h
index de1b98fc86..9e535afdc2 100644
--- a/src/core/SkDescriptor.h
+++ b/src/core/SkDescriptor.h
@@ -32,7 +32,7 @@ public:
     void* operator new(size_t);
     void* operator new(size_t, void* p) { return p; }
 
-    void flatten(SkWriteBuffer& buffer);
+    void flatten(SkWriteBuffer& buffer) const;
 
     uint32_t getLength() const { return fLength; }
     void* addEntry(uint32_t tag, size_t length, const void* data = nullptr);