delete method
Returns a sentinel for use with update() or set() with {merge:true} to mark a field for deletion.
@return The FieldValue sentinel for use in a call to set() or update().
Implementation
external FieldValue delete();
Returns a sentinel for use with update() or set() with {merge:true} to mark a field for deletion.
@return The FieldValue sentinel for use in a call to set() or update().
external FieldValue delete();