update
Updates a credential with partial changes using read-modify-write semantics.
Only non-null fields in the updates object are applied to the existing credential. Uses synchronous SharedPreferences.Editor.commit to ensure atomicity of the read-modify-write operation. A Mutex guards the entire sequence to prevent concurrent modifications.
Parameters
credential
The credential ID to update
updates
The partial updates to apply
Throws
if the credential does not exist
if the update fails