Prevent check recipient valid if empty

And add a catch to fallback + warning if check throwed

src/bridge/LibcoreBridge.js

@@ -52,6 +52,7 @@ const isRecipientValid = (currency, recipient) => {
   const key = `${currency.id}_${recipient}`
   let promise = recipientValidLRU.get(key)
   if (promise) return promise
+  if (!recipient) return Promise.resolve(false)
   promise = libcoreValidAddress
     .send({
       address: recipient,

src/components/modals/Send/fields/RecipientField.js

@@ -3,6 +3,7 @@ import React, { Component } from 'react'
 import type { Account } from '@ledgerhq/live-common/lib/types'
 import type { T } from 'types/common'
 import type { WalletBridge } from 'bridge/types'
+import logger from 'logger'
 import Box from 'components/base/Box'
 import Label from 'components/base/Label'
 import LabelInfoTooltip from 'components/base/LabelInfoTooltip'
@@ -39,12 +40,16 @@ class RecipientField<Transaction> extends Component<Props<Transaction>, { isVali
   async resync() {
     const { account, bridge, transaction } = this.props
     const syncId = ++this.syncId
+    try {
       const isValid = await bridge.isRecipientValid(
         account.currency,
         bridge.getTransactionRecipient(account, transaction),
       )
       if (syncId !== this.syncId) return
       this.setState({ isValid })
+    } catch (err) {
+      logger.warn(`Can't check if recipient is valid`, err)
+    }
   }
 
   onChange = (recipient: string, maybeExtra: ?Object) => {