CE Port of fix for roadmap forward timeline scroll

EE MR: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/9530

app/assets/javascripts/lib/utils/common_utils.js

@@ -130,7 +130,7 @@ export const isInViewport = (el, offset = {}) => {
     rect.top >= (top || 0) &&
     rect.left >= (left || 0) &&
     rect.bottom <= window.innerHeight &&
-    rect.right <= window.innerWidth
+    parseInt(rect.right, 10) <= window.innerWidth
   );
 };
 

spec/javascripts/lib/utils/common_utils_spec.js

@@ -855,6 +855,7 @@ describe('common_utils', () => {
     });
 
     it('returns true when provided `el` is in viewport', () => {
+      el.setAttribute('style', `position: absolute; right: ${window.innerWidth + 0.2};`);
       document.body.appendChild(el);
 
       expect(commonUtils.isInViewport(el)).toBe(true);