FIX "Save" button state

Previously, Save button remains as it is after clicking on it with api call
in background. Now, we enabled loading UI on button when start processing

client/src/legacy/LeftAndMain.js

@@ -460,6 +460,24 @@ $.entwine('ss', function($) {
       // default to first button if none given - simulates browser behaviour
       if(!button) button = this.find('.btn-toolbar :submit:first');
 
+      if ($(button).is("button")) {
+        $(button).append(
+          $(
+            '<div class="btn__loading-icon">' +
+              '<span class="btn__circle btn__circle--1"></span>' +
+              '<span class="btn__circle btn__circle--2"></span>' +
+              '<span class="btn__circle btn__circle--3"></span>' +
+              "</div>"
+          )
+        );
+
+        $(button).css($(button).outerWidth() + "px");
+      }
+
+      // set button to "submitting" state
+      $(button).addClass('btn--loading loading');
+      $(button).prop('disabled', true);
+
       var beforeSubmitFormEventData = {
         // array of promises that must resolve({success:true}) before the form is submitted
         // result of each promise must be an object of
@@ -499,15 +517,12 @@ $.entwine('ss', function($) {
               }
             });
           }
+          clearButton();
           return false;
         }
 
         self.trigger('submitform', {form: form, button: button});
 
-        // set button to "submitting" state
-        $(button).addClass('btn--loading loading');
-        $(button).prop('disabled', true);
-
         if($(button).is('button')) {
 
           $(button).append($(
@@ -572,7 +587,10 @@ $.entwine('ss', function($) {
             newContentEls.filter('form').trigger('aftersubmitform', {status: status, xhr: xhr, formData: formData});
           }
         }, ajaxOptions));
-      });
+      }).catch(function() {
+    		// Handle errors from the promises
+    		clearButton();
+      });;
 
       return false;
     },