$ACTIVE_FIELD: Resizing Grid column fails when it was changed dynamically before

Summary:
When dynamically changing the width of a column in the grid widget by setting
the columnwidth entity property (using $entityproperties) then it's not
possible to resize the column manually when the ASN setting $ACTIVE_FIELD is
used.

Symptoms:
When dynamically changing the width of a column in the grid widget by setting
the columnwidth entity property (using $entityproperties) then it's not
possible to resize the column manually when the ASN setting $ACTIVE_FIELD is
used.

Consider the following scenario:

1. The column width for the field FLD1 (of the Grid entity ENT1) is set to 20
in the Execute trigger

putitem/id $entityproperties(ENT1), "ColumnWidth", "FLD1=20"

2. The form with the Grid is tested using the $ACTIVE_FIELD setting

[SETTINGS]
$active_field=HLT

3. The user tries to resize the column width for FLD1 using the mouse (e.g.
make it wider or smaller)

=> Result: after resizing the column the width is restored to the size
specified before in code (e.g. 20).