Chore: Round timer values to integers (#786)

src/lib/Timer.js

@@ -45,7 +45,7 @@ class Timer {
         }
 
         time.end = global.performance.now();
-        time.elapsed = time.end - time.start;
+        time.elapsed = Math.round(time.end - time.start);
     }
 
     /**

src/lib/__tests__/Timer-test.js

@@ -71,10 +71,10 @@ describe('lib/Timer', () => {
 
         it('should set the end prop, and calculate the elapsed time', () => {
             sandbox.stub(global.performance, 'now').returns(5);
-            Timer.times[tag] = { start: 3 };
+            Timer.times[tag] = { start: 3.5 };
 
             Timer.stop(tag);
-            expect(Timer.get(tag).elapsed).to.equal(2); // 5 - 3 = 2
+            expect(Timer.get(tag).elapsed).to.equal(2); // 5 - 3.5 = 1.5, rounded = 2
         });
     });