Add sk_ref_sp helper function.

include/core/SkRefCnt.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkRefCnt_DEFINED
 #define SkRefCnt_DEFINED
 
 #include "../private/SkAtomics.h"
 #include "../private/SkUniquePtr.h"
 #include "SkTypes.h"
 #include <functional>
 #include <utility>
 
+#define SK_SUPPORT_TRANSITION_TO_SP_INTERFACES
+
 /** \class SkRefCntBase
 
     SkRefCntBase is the base class for objects that may be shared by multiple
     objects. When an existing owner wants to share a reference, it calls ref().
     When an owner wants to release its reference, it calls unref(). When the
     shared object's reference count goes to zero as the result of an unref()
     call, its (virtual) destructor is called. It is an error for the
     destructor to be called explicitly (or via the object going out of scope on
     the stack or calling delete) if getRefCnt() > 1.
 */
@@ skipping 396 matching lines @@
 }
 template <typename T> inline bool operator>=(std::nullptr_t, const sk_sp<T>& b) {
     return !(nullptr < b);
 }
 
 template <typename T, typename... Args>
 sk_sp<T> sk_make_sp(Args&&... args) {
     return sk_sp<T>(new T(std::forward<Args>(args)...));
 }
 
+#ifdef SK_SUPPORT_TRANSITION_TO_SP_INTERFACES
+
+/*
+ *  Returns a sk_sp wrapping the provided ptr AND calls ref on it (if not null).
+ *
+ *  This is different than the semantics of the constructor for sk_sp, which just wraps the ptr,
+ *  effectively "adopting" it.
+ *
+ *  This function may be helpful while we convert callers from ptr-based to sk_sp-based parameters.
+ */
+template <typename T> sk_sp<T> sk_ref_sp(T* obj) {
+    return sk_sp<T>(SkSafeRef(obj));
+}
+
 #endif
+
+#endif