The ImportOKPKeyTask::Init is using the Coerce() function to
determine the operation's parameters based on the algorithm,
which the IDL defines it as an ObjectorString type. However,
the Coerce() function expects the algorithm to be an object,
otherwise it fails with a Syntax Error.
The importKey operation for OKP keys just requires a simple
object {name: AlgorithmId} to build the KeyAlgorithm used as
input parameter. We could just use the GetAlgorithmName function,
already prepared to deal with either Objects or Strings, and
avoid calling to Coerce.
Differential Revision: https://phabricator.services.mozilla.com/D225786
a1b3133968