Fixes undefined scenarious

Resolves brave#11703
Resolves brave#11684

Auditors:

Test Plan:

app/browser/api/ledger.js

@@ -2392,12 +2392,12 @@ const transitionWalletToBat = () => {
   let newPaymentId, result
 
   if (newClient === true) return
+  clientprep()
 
   // Restore newClient from the file
   if (!newClient) {
     const fs = require('fs')
     try {
-      clientprep()
       fs.accessSync(pathName(newClientPath), fs.FF_OK)
       fs.readFile(pathName(newClientPath), (error, data) => {
         if (error) {
@@ -2418,7 +2418,6 @@ const transitionWalletToBat = () => {
   // Create new client
   if (!newClient) {
     try {
-      clientprep()
       newClient = ledgerClient(null, underscore.extend({roundtrip: roundtrip}, clientOptions), null)
       muonWriter(newClientPath, newClient.state)
     } catch (ex) {
@@ -2445,6 +2444,11 @@ const transitionWalletToBat = () => {
     return
   }
 
+  if (!client) {
+    console.log('client error')
+    return
+  }
+
   if (client.busyP()) {
     console.log('ledger client is currently busy; transition will be retried on next launch')
     return