More minor refactorings

Extracted from #7244

Co-authored-by: ivaniskandar <ivaniskandar@users.noreply.github.com>

app/src/main/java/eu/kanade/tachiyomi/ui/browse/migration/search/SearchController.kt

@@ -84,7 +84,7 @@ class SearchController(
         if (!isReplacingManga) {
             router.popController(this)
             if (newManga != null) {
-                val newMangaController = RouterTransaction.with(MangaController(newManga))
+                val newMangaController = RouterTransaction.with(MangaController(newManga.id!!))
                 if (router.backstack.lastOrNull()?.controller is MangaController) {
                     // Replace old MangaController
                     router.replaceTopController(newMangaController)
@@ -140,7 +140,7 @@ class SearchController(
                 }
                 .setNeutralButton(activity?.getString(R.string.action_show_manga)) { _, _ ->
                     dismissDialog()
-                    router.pushController(MangaController(newManga))
+                    router.pushController(MangaController(newManga!!.id!!))
                 }
                 .create()
         }

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt

@@ -575,7 +575,7 @@ open class BrowseSourceController(bundle: Bundle) :
      */
     override fun onItemClick(view: View, position: Int): Boolean {
         val item = adapter?.getItem(position) as? SourceItem ?: return false
-        router.pushController(MangaController(item.manga, true))
+        router.pushController(MangaController(item.manga.id!!, true))
 
         return false
     }

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/globalsearch/GlobalSearchController.kt

@@ -65,7 +65,7 @@ open class GlobalSearchController(
      * @param manga clicked item containing manga information.
      */
     override fun onMangaClick(manga: Manga) {
-        router.pushController(MangaController(manga, true))
+        router.pushController(MangaController(manga.id!!, true))
     }
 
     /**