EDITED 2019-02-08

`maxTxFee` is a global variable, used by both the raw transaction and wallet RPCs. It's set from `-maxtxfee`.

~listed in the global help text in init.cpp, but is only set in `WalletInit::ParameterInteraction()`. If the wallet is disabled, then `-maxtxfee` is ignored and the default is used.~

~This behaviour has existed since the mempool was changed to limit acceptance based on `maxTxFee` in https://github.com/bitcoin/bitcoin/commit/fa331db68bcc68e4c93fb45aaa30f911b0ecfe1a.~

~Short-term fix is to move the `-maxtxfee` handling to `InitParameterInteraction()` in init.cpp.~
EDIT: `maxTxFee` initiation bug fixed in #15357 

I don't think we should share this setting between the node and wallet.
#include <netbase.h>
#include <net.h>
#include <net_processing.h>
#include <policy/feerate.h>
#include <policy/fees.h>
#include <policy/policy.h>
#include <rpc/server.h>
#include <rpc/register.h>
#include <rpc/blockchain.h>
#include <rpc/util.h>
#include <script/standard.h>
#include <script/sigcache.h>
#include <scheduler.h>
#include <shutdown.h>
#include <timedata.h>
#include <txdb.h>
#include <txmempool.h>
#include <torcontrol.h>
#include <ui_interface.h>
#include <util/system.h>
#include <util/moneystr.h>
#include <validationinterface.h>
#include <warnings.h>
#include <walletinitinterface.h>
#include <stdint.h>
#include <stdio.h>
#ifndef WIN32
#include <signal.h>
#include <sys/stat.h>
#endif