Ogg::XiphComment::removeField() crashes if parameter "value" is not the default String::null

[Urs Fleisch]

Ogg::XiphComment::removeField() crashes if parameter "value" is not the  
default String::null. This happens because the iterator "it" becomes  
invalidated after the call to erase().

void Ogg::XiphComment::removeField(const String &key, const String &value)
{
   if(!value.isNull()) {
     StringList::Iterator it = d->fieldListMap[key].begin();
     for(; it != d->fieldListMap[key].end(); ++it) {
       if(value == *it)
         d->fieldListMap[key].erase(it);
     }
   }
   else
     d->fieldListMap.erase(key);
}

To fix it, the iterator has to be incremented before erasing, for example  
like this:

void Ogg::XiphComment::removeField(const String &key, const String &value)
{
   if(!value.isNull()) {
     StringList::Iterator it = d->fieldListMap[key].begin();
     for(; it != d->fieldListMap[key].end();) {
       if(value == *it)
         d->fieldListMap[key].erase(it++);
       else
         ++it;
     }
   }
   else
     d->fieldListMap.erase(key);
}

Regards,
Urs