fix: Resolve load failures for TS-based content on Android-based Cast…

… devices (shaka-project#4569). (shaka-project#4570)

See shaka-project#4569 for more
context.

This affects any Chromecast model which contains the substring `Android`
in their userAgent. For TS content, this causes Shaka to incorrectly
filter all stream variants leaving nothing for the player to select for
playback (resulting in a `4032` error):
https://github.com/shaka-project/shaka-player/blob/757b34e5959f14c9a5b5aed173cc99d98a794a40/lib/util/stream_utils.js#L484-L491.

lib/polyfill/media_capabilities.js

@@ -24,8 +24,9 @@ shaka.polyfill.MediaCapabilities = class {
    * @export
    */
   static install() {
-    // Since MediaCapabilities is not fully supported on some Chromecast yet,
-    // we should always install polyfill for all Chromecast not Android-based.
+    // Since MediaCapabilities implementation is buggy on the Chromecast
+    // platform (see https://github.com/shaka-project/shaka-player/issues/4569),
+    // we should always install polyfills on all Chromecast models.
     // TODO: re-evaluate MediaCapabilities in the future versions of Chromecast.
     // Since MediaCapabilities implementation is buggy in Apple browsers, we
     // should always install polyfill for Apple browsers.
@@ -52,9 +53,6 @@ shaka.polyfill.MediaCapabilities = class {
         shaka.util.Platform.isChromecast()) {
       canUseNativeMCap = false;
     }
-    if (shaka.util.Platform.isAndroidCastDevice()) {
-      canUseNativeMCap = true;
-    }
     if (canUseNativeMCap && navigator.mediaCapabilities) {
       shaka.log.info(
           'MediaCapabilities: Native mediaCapabilities support found.');

lib/util/platform.js

@@ -163,16 +163,6 @@ shaka.util.Platform = class {
     return shaka.util.Platform.userAgentContains_('CrKey');
   }
 
-  /**
-   * Check if the current platform is a Android-based Cast devices.
-   *
-   * @return {boolean}
-   */
-  static isAndroidCastDevice() {
-    return shaka.util.Platform.isChromecast() &&
-        shaka.util.Platform.userAgentContains_('Android');
-  }
-
   /**
    * Returns a major version number for Chrome, or Chromium-based browsers.
    *