Support for Double Field

Problem/Motivation

The popular Double Field module → fields can't be encrypted.

When enabling field encryption to a Douple Field field gives a notice:

Attempt to update field Change date failed: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'node_revision__field_change_date.field_change_date_value' in 'where clause': SELECT "base_table"."vid" AS "vid", "base_table"."nid" AS "nid" FROM "node_revision" "base_table" INNER JOIN "node_revision__field_change_date" "node_revision__field_change_date" ON "node_revision__field_change_date"."revision_id" = "base_table"."vid" WHERE "node_revision__field_change_date"."field_change_date_value" IS NOT NULL; Array ( ) .

Steps to reproduce

• Install and Double Field and configure Field Encrypt module.
• Add a field type Double Field to a Node type. Let's use Article and the field a "Change Date".
• Configure the Double Field subfields: Text and Float. Set "Allowed number of values" to unlimited and name the subfields.
• Create and article with some data in the Double Fields fields.
• Configure encryption and try to turn on the field encryption for the Double Field field.