Issue 5216 - [emscripten] Use a more reliable way of retrieving mangled function name

compiled/bindings/generator.h

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 101 matching lines @@
   char TypeInfo<T>::s_typeIDHelper;
 
   struct FunctionInfo
   {
     TypeCategory returnType;
     TYPEID pointerType;
     std::vector<TypeCategory> args;
     bool instance_function;
     int effectiveArgs;
     TypeCategory effectiveReturnType;
-    char name[1024];
+    std::string name;
 
     FunctionInfo();
 
     FunctionInfo(TypeCategory returnType, TYPEID pointerType,
         std::initializer_list<TypeCategory> argTypes, bool instance_function,
         void* function);
 
     template<typename ReturnType, typename... Args>
     FunctionInfo(ReturnType (*function)(Args...))
         : FunctionInfo(TypeInfo<ReturnType>(),
@@ skipping 204 matching lines @@
 
   template<typename ReturnType, typename... Args>
   namespace_& function(const char* name, ReturnType (*method)(Args...))
   {
     bindings_internal::register_namespace_method(mName, name, method);
     return *this;
   }
 };
 
 void printBindings();