code: function cancel() {
          var self = this;
          return storeTaskRunner.run(function() {
              return store.del(operationTableName, pushOperation.logRecord.id).then(function() {
                  self.isHandled = true;
              });
          });
      }
docs: Cancels pushing the current operation to the server permanently.
  This will also set {@link PushError#isHandled} to true.
  
  This method simply removes the pending operation from the operation table, thereby
  permanently skipping the associated change from being pushed to the server. A future change
  done to the same record will not be affected and such changes will continue to be pushed.
  
  @function
  @instance
  @memberof PushError
  
  @returns {Promise} A promise that is fulfilled when the operation is cancelled OR rejected
  with the error if it fails to cancel it.