matrix-js-sdk

794b8ef2 - crypto-api: add isDehydratedDeviceKeyMissing() to detect an inaccessible dehydrated device

crypto-api: add isDehydratedDeviceKeyMissing() to detect an inaccessible dehydrated device When device dehydration was set up on another of the user's devices, a dehydrated device exists on the server, but a freshly logged-in device may not hold the dehydration key (it is neither cached in the crypto store nor read from Secret Storage). There was no way for a client to detect this in order to prompt the user to recover the key from 4S. Add CryptoApi.isDehydratedDeviceKeyMissing(), implemented in DehydratedDeviceManager: it reports true when the server has a dehydrated device and the dehydration key is not cached locally. Part of element-hq/element-web#29579.