perf(Ads): Reduce latency for interstitial to start playing (shaka-pr…

…oject#7528)

Use requestVideoFrameCallback the achieve better performance

lib/ads/interstitial_ad_manager.js

@@ -106,8 +106,7 @@ shaka.ads.InterstitialAdManager = class {
       }
     });
 
-    /** @private {shaka.util.Timer} */
-    this.timeUpdateTimer_ = new shaka.util.Timer(() => {
+    const checkForInterstitials = () => {
       if (this.playingAd_ || !this.lastTime_ ||
           this.basePlayer_.isRemotePlayback()) {
         return;
@@ -125,7 +124,22 @@ shaka.ads.InterstitialAdManager = class {
         this.setupAd_(currentInterstitial, /* sequenceLength= */ 1,
             /* adPosition= */ 1, /* initialTime= */ Date.now());
       }
-    }).tickEvery(/* seconds= */ 0.025);
+    };
+
+    /** @private {shaka.util.Timer} */
+    this.timeUpdateTimer_ = new shaka.util.Timer(checkForInterstitials);
+
+    if ('requestVideoFrameCallback' in this.baseVideo_ &&
+        !shaka.util.Platform.isSmartTV()) {
+      const baseVideo = /** @type {!HTMLVideoElement} */ (this.baseVideo_);
+      const videoFrameCallback = () => {
+        checkForInterstitials();
+        baseVideo.requestVideoFrameCallback(videoFrameCallback);
+      };
+      baseVideo.requestVideoFrameCallback(videoFrameCallback);
+    } else {
+      this.timeUpdateTimer_.tickEvery(/* seconds= */ 0.025);
+    }
 
     /** @private {shaka.util.Timer} */
     this.pollTimer_ = new shaka.util.Timer(async () => {