Provide proper feedback when creating a share in the webUI

Fixes #22304

Creating a share is not instant (especially not for federated shares) so
we should show that something is happening in the webUI properly.

core/js/sharedialogview.js

@@ -233,8 +233,18 @@
 
 		_onSelectRecipient: function(e, s) {
 			e.preventDefault();
-			$(e.target).val('');
-			this.model.addShare(s.item.value);
+			$(e.target).attr('disabled', true)
+				.val(s.item.label);
+			var $loading = this.$el.find('.shareWithLoading');
+			$loading.removeClass('hidden')
+				.addClass('inlineblock');
+
+			this.model.addShare(s.item.value, {success: function() {
+				$(e.target).val('')
+					.attr('disabled', false);
+				$loading.addClass('hidden')
+					.removeClass('inlineblock');
+			}});
 		},
 
 		_toggleLoading: function(state) {

core/js/shareitemmodel.js

@@ -183,11 +183,9 @@
 				data: attributes,
 				dataType: 'json'
 			}).done(function() {
-				self.fetch({
-					success: function() {
-						if (_.isFunction(options.success)) {
-							options.success(self);
-						}
+				self.fetch().done(function() {
+					if (_.isFunction(options.success)) {
+						options.success(self);
 					}
 				});
 			}).fail(function(xhr) {