Due to a recent change, empty strings are unhandled. This results
in Blender crashing.
This patch fixes the crash but a discrepancy still exists...
Prior to the regression, the empty string would be replaced by the
name of the data type. This patch uses "Attribute" for the default
name regardless of type. Restoring the previous behavior would
require making and/or modifying API methods.
Regression introduced in: rBeae36be372a6
Reviewed By: Joseph Eagar & Campbell Barton
Differential Revision: https://developer.blender.org/D14734
Ref D14734
177bc80748