fix: Timeout unfulfilled request to decodingInfo and requestMediaKeyS…

…ystemAccess

On some (Android) WebView environments,
decodingInfo and requestMediaKeySystemAccess will
not resolve or reject, at least if RESOURCE_PROTECTED_MEDIA_ID
is not set.  This is a workaround for that issue.

lib/media/drm_engine.js

@@ -1870,8 +1870,27 @@ shaka.media.DrmEngine = class {
         offlineConfig.sessionTypes = ['persistent-license'];
 
         const configs = [offlineConfig, basicConfig];
-
-        const access = await navigator.requestMediaKeySystemAccess(
+        // On some (Android) WebView environments,
+        // requestMediaKeySystemAccess will
+        // not resolve or reject, at least if RESOURCE_PROTECTED_MEDIA_ID
+        // is not set.  This is a workaround for that issue.
+        const TIMEOUT_FOR_CHECKACCESS_IN_SECONDS = 1;
+        const checkAccessOrTimeout = (keySystem, configs) => {
+          return new Promise((resolve, reject) => {
+            let resolved = false;
+            navigator.requestMediaKeySystemAccess(keySystem, configs)
+                .then((access) => {
+                  resolved = true;
+                  resolve(access);
+                });
+            new shaka.util.Timer(() => {
+              if (!resolved) {
+                reject(new Error('Timeout requestMediaKeySystemAccess'));
+              }
+            }).tickAfter(TIMEOUT_FOR_CHECKACCESS_IN_SECONDS);
+          });
+        };
+        const access = await checkAccessOrTimeout(
             keySystem, configs);
         await processMediaKeySystemAccess(keySystem, access);
       } catch (error) {}  // Ignore errors.
@@ -1907,13 +1926,34 @@ shaka.media.DrmEngine = class {
             },
           },
         };
-
+        // On some (Android) WebView environments, decodingInfo will
+        // not resolve or reject, at least if RESOURCE_PROTECTED_MEDIA_ID
+        // is not set.  This is a workaround for that issue.
+        const TIMEOUT_FOR_DECODING_INFO_IN_SECONDS = 1;
+        const decodeOrTimeout = (decodingConfig) => {
+          return new Promise((resolve, reject) => {
+            let resolved = false;
+            navigator.mediaCapabilities.decodingInfo(decodingConfig)
+                .then((result) => {
+                  resolved = true;
+                  resolve(result);
+                });
+            new shaka.util.Timer(() => {
+              if (!resolved) {
+                reject(new Error('Timeout decodingInfo'));
+              }
+            }).tickAfter(TIMEOUT_FOR_DECODING_INFO_IN_SECONDS);
+          });
+        };
         const decodingInfo =
-            await navigator.mediaCapabilities.decodingInfo(decodingConfig);
+            await decodeOrTimeout(decodingConfig);
 
         const access = decodingInfo.keySystemAccess;
         await processMediaKeySystemAccess(keySystem, access);
-      } catch (error) {}  // Ignore errors.
+      } catch (error) {
+        // Ignore errors.
+        shaka.log.v2('Failed to probe support for', keySystem, error);
+      }
     };
 
     // Initialize the support structure for each key system.