Use a single place to create values for bool custom fields

modules/webapp/src/main/elm/Comp/CustomFieldInput.elm

@@ -24,6 +24,7 @@ import Html.Attributes exposing (..)
 import Html.Events exposing (onClick, onInput)
 import Messages.Comp.CustomFieldInput exposing (Texts)
 import Styles as S
+import Util.CustomField
 import Util.Maybe
 
 
@@ -267,18 +268,11 @@ update1 forSearch msg model =
 
         ( ToggleBool, BoolField b ) ->
             let
-                notb =
-                    not b
-
                 model_ =
-                    { model | fieldModel = BoolField notb }
+                    { model | fieldModel = BoolField (not b) }
 
                 value =
-                    if notb then
-                        "true"
-
-                    else
-                        "false"
+                    Util.CustomField.boolValue (not b)
             in
             UpdateResult model_ Cmd.none (Value value)
 

modules/webapp/src/main/elm/Comp/CustomFieldMultiInput.elm

@@ -222,7 +222,7 @@ update1 forSearch flags msg model =
                 change =
                     case Data.CustomFieldType.fromString f.ftype of
                         Just Data.CustomFieldType.Boolean ->
-                            FieldValueChange f "false"
+                            FieldValueChange f (Util.CustomField.boolValue False)
 
                         _ ->
                             NoFieldChange

modules/webapp/src/main/elm/Util/CustomField.elm

@@ -1,5 +1,6 @@
 module Util.CustomField exposing
-    ( nameOrLabel
+    ( boolValue
+    , nameOrLabel
     , renderValue
     , renderValue2
     )
@@ -12,6 +13,17 @@ import Html.Attributes exposing (..)
 import Html.Events exposing (onClick)
 
 
+{-| This is how the server wants the value to a bool custom field
+-}
+boolValue : Bool -> String
+boolValue b =
+    if b then
+        "true"
+
+    else
+        "false"
+
+
 nameOrLabel : { r | name : String, label : Maybe String } -> String
 nameOrLabel fv =
     Maybe.withDefault fv.name fv.label