New Web Layout (#2126)

* Rip out virtualization on the web

* Screw around with layout

* onEndReached

* scrollToOffset

* Fix background

* onScroll

* Shell bars

* More scroll

* Fixes

* position: sticky

* Clean up 1

* Clean up 2

* Undo PagerWithHeader changes and fork it

* Trim down both versions

* Cleanup 3

* Memoize, lint

* Don't scroll away modal or lightbox

* Add content-visibility for rows

* Fix composer

* Fix types

* Fix borked scroll animation

* Fixes to layout

* More FlatList parity

* Layout fixes

* Fix more layout

* More layout

* More layouts

* Fix profile layout

* Remove onScroll

* Display: none inactive pages

* Add an intermediate List component

* Fix type

* Add onScrolledDownChange

* Port pager to use onScrolledDownChange

* Fix on mobile

* Don't pass down onScroll (replacement TBD)

* Remove resetMainScroll

* Replace onMainScroll with MainScrollProvider

* Hook ScrollProvider to pager

* Fix the remaining special case

* Optimize a bit

* Enforce that onScroll cannot be passed

* Keep value updated even if no handler

* Also memo it

* Move the fork to List.web

* Add scroll handler

* Consolidate List props a bit

* More stuff

* Rm unused

* Simplify

* Make isScrolledDown work

* Oops

* Fixes

* Hook up context scroll handlers

* Scroll restore for tabs

* Route scroll restoration POC

* Fix some issues with restoration

* Remove bad idea

* Fix pager scroll restoration

* Undo accidental locale changes

* onContentSizeChange

* Scroll to post

* Better positioning

* Layout fixes

* Factor out navigation stuff

* Cleanup

* Oops

* Cleanup

* Fixes and types

* Naming etc

* Fix crash

* Match FL semantics

* Snap the header scroll on the web

* Add body scroll lock

* Scroll to top on search

* Fix types

* Typos

* Fix Safari overflow

* Fix search positioning

* Add border

* Patch react navigation

* Revert "Patch react navigation"

This reverts commit 62516ed9c2.

* fixes

* scroll

* scrollbar

* cleanup unrelated

* undo unrel

* flatter

* Fix css

* twk

src/Navigation.tsx

@@ -39,6 +39,7 @@ import {
   setEmailConfirmationRequested,
 } from './state/shell/reminders'
 import {init as initAnalytics} from './lib/analytics/analytics'
+import {useWebScrollRestoration} from './lib/hooks/useWebScrollRestoration'
 
 import {HomeScreen} from './view/screens/Home'
 import {SearchScreen} from './view/screens/Search'
@@ -413,10 +414,12 @@ function MyProfileTabNavigator() {
 const FlatNavigator = () => {
   const pal = usePalette('default')
   const numUnread = useUnreadNotifications()
-
+  const screenListeners = useWebScrollRestoration()
   const title = (page: MessageDescriptor) => bskyTitle(i18n._(page), numUnread)
+
   return (
     <Flat.Navigator
+      screenListeners={screenListeners}
       screenOptions={{
         gestureEnabled: true,
         fullScreenGestureEnabled: true,