import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/base/BorrowedAttrInfo.h

@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BorrowedAttrInfo_h__
+#define BorrowedAttrInfo_h__
+
+#include "mozilla/Assertions.h"
+
+class nsAttrName;
+class nsAttrValue;
+
+namespace mozilla {
+namespace dom {
+
+/**
+ * Struct that stores info on an attribute. The name and value must either both
+ * be null or both be non-null.
+ *
+ * Note that, just as the pointers returned by GetAttrNameAt, the pointers that
+ * this struct hold are only valid until the element or its attributes are
+ * mutated (directly or via script).
+ */
+struct BorrowedAttrInfo
+{
+  BorrowedAttrInfo()
+    : mName(nullptr)
+    , mValue(nullptr)
+  {
+  }
+
+  BorrowedAttrInfo(const nsAttrName* aName, const nsAttrValue* aValue);
+
+  BorrowedAttrInfo(const BorrowedAttrInfo& aOther);
+
+  const nsAttrName* mName;
+  const nsAttrValue* mValue;
+
+  explicit operator bool() const { return mName != nullptr; }
+};
+
+} // namespace dom
+} // namespace mozilla
+#endif