FIX: display error message when upload fails in wizard

app/assets/javascripts/wizard/components/wizard-field-image.js.es6

@@ -38,5 +38,21 @@ export default Ember.Component.extend({
       this.set("field.value", response.result.url);
       this.set("uploading", false);
     });
+
+    $upload.on("fileuploadfail", (e, response) => {
+      let message = I18n.t("wizard.upload_error")
+      if (response.jqXHR.responseJSON && response.jqXHR.responseJSON.errors) {
+        message = response.jqXHR.responseJSON.errors.join("\n");
+      }
+
+      window.swal({
+        customClass: "wizard-warning",
+        title: "",
+        text: message,
+        type: "warning",
+        confirmButtonColor: "#6699ff"
+      });
+      this.set("uploading", false);
+    });
   }
 });

config/locales/client.en.yml

@@ -3949,6 +3949,7 @@ en:
       step: "%{current} of %{total}"
       upload: "Upload"
       uploading: "Uploading..."
+      upload_error: "Sorry, there was an error uploading that file. Please try again."
       quit: "Maybe Later"
 
       staff_count:

config/locales/server.en.yml

@@ -3860,7 +3860,7 @@ en:
         fields:
           favicon_url:
             label: "Small Icon"
-            description: "Icon image used to represent your site in web browsers that looks good at small sizes such as 32px by 32px."
+            description: "Icon image used to represent your site in web browsers that looks good at small sizes such as 32px by 32px. Recommended image extensions are PNG or JPG."
           apple_touch_icon_url:
             label: "Large Icon"
             description: "Icon image used to represent your site on modern devices that looks good at larger sizes. Recommended size is at least 512px by 512px."