Require SK_DECLARE_STATIC_LAZY_PTR is used in global scope.

src/core/SkData.cpp

Index: src/core/SkData.cpp
diff --git a/src/core/SkData.cpp b/src/core/SkData.cpp
index 11cab7e98be73388c67bfecc2845dd8c1278ea92..c5d10775f8024cad028c69dbb7e107325c157586 100644
--- a/src/core/SkData.cpp
+++ b/src/core/SkData.cpp
@@ -92,14 +92,13 @@ SkData* SkData::PrivateNewWithCopy(const void* srcOrNull, size_t length) {
 
 ///////////////////////////////////////////////////////////////////////////////
 
-SkData* SkData::NewEmptyImpl() {
-    return new SkData(NULL, 0, NULL, NULL);
-}
+// As a template argument these must have external linkage.
+SkData* sk_new_empty_data() { return new SkData(NULL, 0, NULL, NULL); }
+namespace { void sk_unref_data(SkData* ptr) { return SkSafeUnref(ptr); } }
 
-void SkData::DeleteEmpty(SkData* ptr) { SkDELETE(ptr); }
+SK_DECLARE_STATIC_LAZY_PTR(SkData, empty, sk_new_empty_data, sk_unref_data);
 
 SkData* SkData::NewEmpty() {
-    SK_DECLARE_STATIC_LAZY_PTR(SkData, empty, NewEmptyImpl, DeleteEmpty);
     return SkRef(empty.get());
 }