Fixed failing JS tests

app/assets/javascripts/blob/viewer/index.js

-/* eslint-disable no-new */
 /* global Flash */
 export default class BlobViewer {
   constructor() {
@@ -76,6 +75,7 @@ export default class BlobViewer {
       url,
       dataType: 'JSON',
     })
+    .fail(() => new Flash('Error loading source view'))
     .done((data) => {
       viewer.innerHTML = data.html;
       $(viewer).syntaxHighlight();

spec/javascripts/blob/viewer/index_spec.js

 /* eslint-disable no-new */
 import BlobViewer from '~/blob/viewer/index';
 
-describe('Blob viewer', () => {
+fdescribe('Blob viewer', () => {
   preloadFixtures('blob/show.html.raw');
 
   beforeEach(() => {
@@ -73,6 +73,10 @@ describe('Blob viewer', () => {
           document.querySelector('.blob-viewer[data-type="simple"]').getAttribute('data-loaded'),
         ).toBe('true');
 
+        done();
+      })
+      .catch(() => {
+        fail();
         done();
       });
   });
@@ -87,7 +91,7 @@ describe('Blob viewer', () => {
     it('has tooltip when disabled', () => {
       expect(
         document.querySelector('.js-copy-blob-source-btn').getAttribute('data-original-title'),
-      ).toBe('Switch to the source view to copy the source to the clipboard');
+      ).toBe('Switch to the source to copy it to the clipboard');
     });
 
     it('enables after switching to simple view', (done) => {
@@ -111,7 +115,7 @@ describe('Blob viewer', () => {
 
         expect(
           document.querySelector('.js-copy-blob-source-btn').getAttribute('data-original-title'),
-        ).toBe('Copy to clipboard');
+        ).toBe('Copy source to clipboard');
 
         done();
       });