Use nullptr instead of 0 in xml and xmlhttprequest.

Source/core/xml/XSLTUnicodeSort.cpp

Index: Source/core/xml/XSLTUnicodeSort.cpp
diff --git a/Source/core/xml/XSLTUnicodeSort.cpp b/Source/core/xml/XSLTUnicodeSort.cpp
index 9c343eb6a1785418a83ae7b1ec51b67b1848fd1c..48044c14e0eefed68ddd82cb8336fc01e1733388 100644
--- a/Source/core/xml/XSLTUnicodeSort.cpp
+++ b/Source/core/xml/XSLTUnicodeSort.cpp
@@ -51,8 +51,8 @@ void xsltUnicodeSortFunction(xsltTransformContextPtr ctxt, xmlNodePtr *sorts, in
     xsltStylePreCompPtr comp;
 #endif
     xmlXPathObjectPtr* resultsTab[XSLT_MAX_SORT];
-    xmlXPathObjectPtr* results = 0;
-    xmlNodeSetPtr list = 0;
+    xmlXPathObjectPtr* results = nullptr;
+    xmlNodeSetPtr list = nullptr;
     int depth;
     xmlNodePtr node;
     int tempstype[XSLT_MAX_SORT], temporder[XSLT_MAX_SORT];