fix flow

src/commands/libcoreScanAccounts.js

@@ -21,8 +21,17 @@ const cmd: Command<Input, Result> = createCommand(
       scanAccountsOnDevice({
         devicePath,
         currencyId,
-        onAccountScanned: account => o.next(account),
-      }).then(() => o.complete(), e => o.error(e))
+        onAccountScanned: account => {
+          o.next(account)
+        },
+      }).then(
+        () => {
+          o.complete()
+        },
+        e => {
+          o.error(e)
+        },
+      )
 
       function unsubscribe() {
         // FIXME not implemented

src/helpers/libcore.js

@@ -18,7 +18,7 @@ import type { NJSAccount, NJSOperation } from '@ledgerhq/ledger-core/src/ledgerc
 type Props = {
   devicePath: string,
   currencyId: string,
-  onAccountScanned: AccountRaw => *,
+  onAccountScanned: AccountRaw => void,
 }
 
 export function scanAccountsOnDevice(props: Props): Promise<AccountRaw[]> {