[enh] Add default icon for alert

app/src/components/globals/formItems/ReadOnlyAlertItem.vue

@@ -1,6 +1,6 @@
 <template>
   <b-alert :variant="type" show>
-    <icon :iname="icon" />
+    <icon :iname="icon_" />
     {{ label }}
   </b-alert>
 </template>
@@ -9,6 +9,18 @@
 export default {
   name: 'ReadOnlyAlertItem',
 
+  data () {
+    let icons = {
+      success: 'thumbs-up',
+      info: 'info',
+      warning: 'warning',
+      danger: 'ban'
+      }
+    return {
+      icon_: (this.icon) ? this.icon : icons[this.type]
+    }
+  },
+
   props: {
     id: { type: String, default: null },
     label: { type: String, default: null },

app/src/helpers/yunohostArguments.js

@@ -56,7 +56,7 @@ export function adressToFormValue (address) {
  * @return {Object} an formated argument containing formItem props, validation and base value.
  */
 export function formatYunoHostArgument (arg) {
-  let value = (arg.value !== undefined) ? arg.value : null
+  let value = (arg.value !== undefined) ? arg.value : (arg.current_value !== undefined) ? arg.current_value : null
   const validation = {}
   arg.ask = formatI18nField(arg.ask)
   const field = {