fixes size of the download spinner

apps/files/js/fileactions.js

 	OCA.Files.FileActions.updateFileActionSpinner = function($downloadButtonElement, showIt) {
 		var $icon = $downloadButtonElement.find('.icon');
 		if (showIt) {
-			var $loadingIcon = $('<span class="icon loading"></span>');
+			var $loadingIcon = $('<span class="icon icon-loading-small"></span>');
 			$icon.after($loadingIcon);
 			$icon.addClass('hidden');
 		} else {
-			$downloadButtonElement.find('.loading').remove();
+			$downloadButtonElement.find('.icon-loading-small').remove();
 			$downloadButtonElement.find('.icon').removeClass('hidden');
 		}
 	};

apps/files/tests/js/fileactionsSpec.js

 
 		it('replaces download icon with spinner', function() {
 			FileActions.updateFileActionSpinner($el, true);
-			expect($el.find('.icon.loading').length).toEqual(1);
+			expect($el.find('.icon.icon-loading-small').length).toEqual(1);
 			expect($el.find('.icon.icon-download').hasClass('hidden')).toEqual(true);
 		});
 		it('replaces spinner back with download icon with spinner', function() {
 			FileActions.updateFileActionSpinner($el, true);
 			FileActions.updateFileActionSpinner($el, false);
-			expect($el.find('.icon.loading').length).toEqual(0);
+			expect($el.find('.icon.icon-loading-small').length).toEqual(0);
 			expect($el.find('.icon.icon-download').hasClass('hidden')).toEqual(false);
 		});
 	});