Fix Android composer padding: Director's Cut (#7412)

* fix android 15 composer padding

* while I'm here, alf some bits and pieces

* add comments

src/view/shell/Composer.web.tsx

@@ -25,7 +25,7 @@ export function Composer({}: {winHeight: number}) {
   // =
 
   if (!isActive) {
-    return <View />
+    return null
   }
 
   return (