Make XPathFunction map use non-static table of FunctionMapping

Source/core/xml/XPathFunctions.cpp

 /*
  * Copyright (C) 2005 Frerich Raabe <raabe@kde.org>
  * Copyright (C) 2006, 2009 Apple Inc.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
@@ skipping 689 matching lines @@
     return round(arg(0)->evaluate(context).toNumber());
 }
 
 struct FunctionMapping {
     const char* name;
     FunctionRec function;
 };
 
 static void createFunctionMap()
 {
-    static const FunctionMapping functions[] = {
+    ASSERT(!functionMap);
+    const FunctionMapping functions[] = {
         { "boolean", { &createFunBoolean, 1 } },
         { "ceiling", { &createFunCeiling, 1 } },
         { "concat", { &createFunConcat, Interval(2, Interval::Inf) } },
         { "contains", { &createFunContains, 2 } },
         { "count", { &createFunCount, 1 } },
         { "false", { &createFunFalse, 0 } },
         { "floor", { &createFunFloor, 1 } },
         { "id", { &createFunId, 1 } },
         { "lang", { &createFunLang, 1 } },
         { "last", { &createFunLast, 0 } },
@@ skipping 23 matching lines @@
 
 
 Function* createFunction(const String& name)
 {
     HeapVector<Member<Expression>> args;
     return createFunction(name, args);
 }
 
 Function* createFunction(const String& name, HeapVector<Member<Expression>>& args)
 {
     if (!functionMap)

[vivekg, 2015/09/02 10:15:40]

The check here makes sure the function |createFunctionMap| is being called only
once.

         createFunctionMap();
 
     HashMap<String, FunctionRec>::iterator functionMapIter = functionMap->find(name);
     FunctionRec* functionRec = nullptr;
 
     if (functionMapIter == functionMap->end() || !(functionRec = &functionMapIter->value)->args.contains(args.size()))
         return nullptr;
 
     Function* function = functionRec->factoryFn();
     function->setArguments(args);
     function->setName(name);
     return function;
 }
 
 }
 }