import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/xslt/xpath/txErrorExpr.cpp

@@ -0,0 +1,43 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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/. */
+
+#include "nsError.h"
+#include "txExpr.h"
+#include "nsString.h"
+#include "txIXPathContext.h"
+
+nsresult
+txErrorExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)
+{
+    *aResult = nullptr;
+
+    nsAutoString err(NS_LITERAL_STRING("Invalid expression evaluated"));
+#ifdef TX_TO_STRING
+    err.AppendLiteral(": ");
+    toString(err);
+#endif
+    aContext->receiveError(err,
+                           NS_ERROR_XPATH_INVALID_EXPRESSION_EVALUATED);
+
+    return NS_ERROR_XPATH_INVALID_EXPRESSION_EVALUATED;
+}
+
+TX_IMPL_EXPR_STUBS_0(txErrorExpr, ANY_RESULT)
+
+bool
+txErrorExpr::isSensitiveTo(ContextSensitivity aContext)
+{
+    // It doesn't really matter what we return here, but it might
+    // be a good idea to try to keep this as unoptimizable as possible
+    return true;
+}
+
+#ifdef TX_TO_STRING
+void
+txErrorExpr::toString(nsAString& aStr)
+{
+    aStr.Append(mStr);
+}
+#endif