fix: Fix detection of spatial rendering support in Cast (#6138)

See https://developers.google.com/cast/docs/media#audio_passthrough

Author: avelad

lib/polyfill/media_capabilities.js

@@ -141,8 +141,15 @@ shaka.polyfill.MediaCapabilities = class {
       }
 
       if (audioConfig) {
-        const contentType = audioConfig.contentType;
-        const isSupported = Capabilities.isTypeSupported(contentType);
+        let isSupported;
+        if (shaka.util.Platform.isChromecast() &&
+            audioConfig.spatialRendering) {
+          const extendedType =
+              audioConfig.contentType + '; spatialRendering=true';
+          isSupported = Capabilities.isTypeSupported(extendedType);
+        } else {
+          isSupported = Capabilities.isTypeSupported(audioConfig.contentType);
+        }
         if (!isSupported) {
           return res;
         }

test/polyfill/media_capabilities_unit.js

@@ -196,8 +196,10 @@ describe('MediaCapabilities', () => {
           await navigator.mediaCapabilities.decodingInfo(mockDecodingConfig);
 
           expect(mockCanDisplayType).not.toHaveBeenCalled();
-          // 1 (during install()) + 1 (for video config check).
-          expect(isChromecastSpy).toHaveBeenCalledTimes(2);
+          // 1 (during install()) +
+          // 1 (for video config check) +
+          // 1 (for audio config check).
+          expect(isChromecastSpy).toHaveBeenCalledTimes(3);
           // 1 (fallback in canCastDisplayType()) +
           // 1 (mockDecodingConfig.audio).
           expect(supportMap.has(mockDecodingConfig.video.contentType))
@@ -219,8 +221,10 @@ describe('MediaCapabilities', () => {
           await navigator.mediaCapabilities.decodingInfo(mockDecodingConfig);
 
           expect(mockCanDisplayType).not.toHaveBeenCalled();
-          // 1 (during install()) + 1 (for video config check).
-          expect(isChromecastSpy).toHaveBeenCalledTimes(2);
+          // 1 (during install()) +
+          // 1 (for video config check) +
+          // 1 (for audio config check).
+          expect(isChromecastSpy).toHaveBeenCalledTimes(3);
           // 1 (fallback in canCastDisplayType()) +
           // 1 (mockDecodingConfig.audio).
           expect(supportMap.has(mockDecodingConfig.video.contentType))
@@ -266,8 +270,10 @@ describe('MediaCapabilities', () => {
       shaka.polyfill.MediaCapabilities.install();
       await navigator.mediaCapabilities.decodingInfo(mockDecodingConfig);
 
-      // 1 (during install()) + 1 (for video config check).
-      expect(isChromecastSpy).toHaveBeenCalledTimes(2);
+      // 1 (during install()) +
+      // 1 (for video config check) +
+      // 1 (for audio config check).
+      expect(isChromecastSpy).toHaveBeenCalledTimes(3);
       // 1 (mockDecodingConfig.audio).
       expect(supportMap.has(chromecastType)).toBe(true);
       // Called once in canCastDisplayType.