Fix browser back button to restore scroll state

Removes the url parameter that was used to identify the card to scroll
to and instead use the id from the internal model.

modules/webapp/src/main/elm/Page/Home/Data.elm

@@ -41,6 +41,7 @@ type alias Model =
     , searchTypeForm : SearchType
     , contentOnlySearch : Maybe String
     , dragDropData : DD.DragDropData
+    , scrollToCard : Maybe String
     }
 
 
@@ -70,6 +71,7 @@ init flags =
     , contentOnlySearch = Nothing
     , dragDropData =
         DD.DragDropData DD.init Nothing
+    , scrollToCard = Nothing
     }
 
 
@@ -98,7 +100,7 @@ type Msg
     | KeyUpMsg (Maybe KeyCode)
     | SetContentOnly String
     | ScrollResult (Result Dom.Error ())
-    | ClearItemDetailId (Maybe String)
+    | ClearItemDetailId
 
 
 type SearchType

modules/webapp/src/main/elm/Page/Home/Update.elm

@@ -243,18 +243,12 @@ update mId key flags settings msg model =
         ScrollResult _ ->
             let
                 cmd =
-                    Process.sleep 800 |> Task.perform (always (ClearItemDetailId mId))
+                    Process.sleep 800 |> Task.perform (always ClearItemDetailId)
             in
             withSub ( model, cmd )
 
-        ClearItemDetailId id ->
-            -- if user clicks quickly away (e.g. on another item), the
-            -- deferred command should be ignored
-            if mId == id then
-                noSub ( model, Page.set key (HomePage Nothing) )
-
-            else
-                noSub ( model, Cmd.none )
+        ClearItemDetailId ->
+            noSub ( { model | scrollToCard = Nothing }, Cmd.none )
 
 
 
@@ -269,7 +263,10 @@ scrollToCard mId model =
     in
     case mId of
         Just id ->
-            ( model, Task.attempt ScrollResult (scroll id), Sub.none )
+            ( { model | scrollToCard = mId }
+            , Task.attempt ScrollResult (scroll id)
+            , Sub.none
+            )
 
         Nothing ->
             ( model, Cmd.none, Sub.none )

modules/webapp/src/main/elm/Page/Home/View.elm

@@ -82,7 +82,7 @@ view current flags settings model =
             ]
             [ viewSearchBar flags model
             , Html.map ItemCardListMsg
-                (Comp.ItemCardList.view current settings model.itemListModel)
+                (Comp.ItemCardList.view model.scrollToCard settings model.itemListModel)
             ]
         , div
             [ classList