crypto: account for disabled SharedArrayBuffer

PR-URL: #50034
Reviewed-By: Filip Skokan <[email protected]>
Reviewed-By: Matthew Aitken <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Yagiz Nizipli <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: codebytere

lib/internal/crypto/webidl.js

@@ -184,7 +184,10 @@ function isNonSharedArrayBuffer(V) {
 }
 
 function isSharedArrayBuffer(V) {
-  return ObjectPrototypeIsPrototypeOf(SharedArrayBuffer.prototype, V);
+  // SharedArrayBuffers can be disabled with --no-harmony-sharedarraybuffer.
+  if (SharedArrayBuffer !== undefined)
+    return ObjectPrototypeIsPrototypeOf(SharedArrayBuffer.prototype, V);
+  return false;
 }
 
 converters.Uint8Array = (V, opts = kEmptyObject) => {