test: Fix playback timeouts on ChromeMac (shaka-project#4520)

Shorten a StreamingEngine integration test to work around an issue with
ChromeMac where playback doesn't always occur at 1x. This is an issue
with Selenium or Chrome itself (unknown) that is out of our control. By
making the test somewhat shorter, we can have it complete on time, even
when this issue is present on a device.

Also increase timeouts on offline playback tests.

test/media/streaming_engine_integration.js

@@ -90,26 +90,26 @@ describe('StreamingEngine', () => {
 
     segmentAvailability = {
       start: 0,
-      end: 60,
+      end: 40,
     };
 
     timeline = shaka.test.StreamingEngineUtil.createFakePresentationTimeline(
         segmentAvailability,
-        /* presentationDuration= */ 60,
+        /* presentationDuration= */ 40,
         /* maxSegmentDuration= */ metadata.video.segmentDuration,
         /* isLive= */ false);
 
     setupNetworkingEngine(
-        /* presentationDuration= */ 60,
+        /* presentationDuration= */ 40,
         {
           audio: metadata.audio.segmentDuration,
           video: metadata.video.segmentDuration,
         });
 
     setupManifest(
         /* firstPeriodStartTime= */ 0,
-        /* secondPeriodStartTime= */ 30,
-        /* presentationDuration= */ 60);
+        /* secondPeriodStartTime= */ 20,
+        /* presentationDuration= */ 40);
 
     setupPlayhead();
 
@@ -263,10 +263,11 @@ describe('StreamingEngine', () => {
       streamingEngine.switchVariant(variant);
       await streamingEngine.start();
       video.play();
-      // The overall test timeout is 120 seconds, and the content is 60
+      // The overall test timeout is 120 seconds, and the content is 40
       // seconds.  It should be possible to complete this test in 100 seconds,
       // and if not, we want the error thrown to be within the overall test's
-      // timeout window.
+      // timeout window.  Note that we have seen some devices fail to play at
+      // full speed for reasons beyond our control, so we plan for >= 0.5x.
       await waiter.timeoutAfter(100).waitForEnd(video);
     });
 

test/offline/offline_integration.js

@@ -68,7 +68,7 @@ filterDescribe('Offline', supportsStorage, () => {
     await player.load(contentUri);
 
     video.play();
-    await playTo(/* end= */ 3, /* timeout= */ 10);
+    await playTo(/* end= */ 3, /* timeout= */ 20);
     await player.unload();
     await storage.remove(contentUri);
   });
@@ -104,7 +104,7 @@ filterDescribe('Offline', supportsStorage, () => {
         await player.load(contentUri);
 
         video.play();
-        await playTo(/* end= */ 3, /* timeout= */ 10);
+        await playTo(/* end= */ 3, /* timeout= */ 20);
         await player.unload();
         await storage.remove(contentUri);
       });
@@ -147,7 +147,7 @@ filterDescribe('Offline', supportsStorage, () => {
         await player.load(contentUri);
 
         video.play();
-        await playTo(/* end= */ 3, /* timeout= */ 10);
+        await playTo(/* end= */ 3, /* timeout= */ 20);
         await player.unload();
         await storage.remove(contentUri);
       });