Port uses of SkLazyPtr to SkOncePtr.

src/core/SkData.cpp

Index: src/core/SkData.cpp
diff --git a/src/core/SkData.cpp b/src/core/SkData.cpp
index 9e65d2a32e28506b34282e1b8872619bff8e1c5d..017c397bbf71732b859a46acb398a1fc1607702d 100644
--- a/src/core/SkData.cpp
+++ b/src/core/SkData.cpp
@@ -6,8 +6,8 @@
  */
 
 #include "SkData.h"
-#include "SkLazyPtr.h"
 #include "SkOSFile.h"
+#include "SkOncePtr.h"
 #include "SkReadBuffer.h"
 #include "SkStream.h"
 #include "SkWriteBuffer.h"
@@ -80,14 +80,9 @@ SkData* SkData::PrivateNewWithCopy(const void* srcOrNull, size_t length) {
 
 ///////////////////////////////////////////////////////////////////////////////
 
-// As a template argument these must have external linkage.
-SkData* sk_new_empty_data() { return new SkData(nullptr, 0, nullptr, nullptr); }
-namespace { void sk_unref_data(SkData* ptr) { return SkSafeUnref(ptr); } }
-
-SK_DECLARE_STATIC_LAZY_PTR(SkData, empty, sk_new_empty_data, sk_unref_data);
-
+SK_DECLARE_STATIC_ONCE_PTR(SkData, gEmpty);
 SkData* SkData::NewEmpty() {
-    return SkRef(empty.get());
+    return SkRef(gEmpty.get([]{return new SkData(nullptr, 0, nullptr, nullptr); }));
 }
 
 // assumes fPtr was allocated via sk_malloc