fix: Duplicate timelineregion* events fired for the same event id (#8013)

Fixes #8009

Author: avelad

lib/media/region_timeline.js

@@ -102,13 +102,14 @@ shaka.media.RegionTimeline = class extends shaka.util.FakeEventTarget {
    * @private
    */
   findSimilarRegion_(region) {
+    const isDiffNegligible = (a, b) => Math.abs(a - b) < 0.1;
     for (const existing of this.regions_) {
       // The same scheme ID and time range means that it is similar-enough to
       // be the same region.
       const isSimilar = existing.schemeIdUri == region.schemeIdUri &&
-                        existing.id == region.id &&
-                        existing.startTime == region.startTime &&
-                        existing.endTime == region.endTime;
+          existing.id == region.id &&
+          isDiffNegligible(existing.startTime, region.startTime) &&
+          isDiffNegligible(existing.endTime, region.endTime);
 
       if (isSimilar) {
         return existing;