Do not pass ReactContext to getViewManagersMap (#44379)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/44379

A common pattern to implement `ViewManagerOnDemandReactPackage` is to use a `getViewManagersMap` helper. If we capture `ReactApplicationContext` there, we will indefinitely retain the the very first ReactApplicationContext, and break/leak across reloads. Instead we should pass the `ReactApplicationContext` whenever we construct the ViewManager.

Changelog: [Internal]

Reviewed By: RSNara

Differential Revision: D56838427

fbshipit-source-id: 76583dd7f5564ed29f0dbfcef33d8d288cbb90e0

packages/react-native-popup-menu-android/android/src/main/java/com/facebook/react/popupmenu/PopupMenuPackage.kt

@@ -18,35 +18,29 @@ import com.facebook.react.uimanager.ViewManager
 
 @ReactModuleList(nativeModules = arrayOf())
 public class PopupMenuPackage() : BaseReactPackage(), ViewManagerOnDemandReactPackage {
-  private var viewManagersMap: Map<String, ModuleSpec>? = null
+  private val viewManagersMap: Map<String, ModuleSpec> =
+      mapOf(
+          ReactPopupMenuManager.REACT_CLASS to
+              ModuleSpec.viewManagerSpec({ ReactPopupMenuManager() }),
+      )
 
   override fun getModule(name: String, context: ReactApplicationContext): NativeModule? {
     return null
   }
 
-  private fun getViewManagersMap(): Map<String, ModuleSpec> {
-    val viewManagers =
-        viewManagersMap
-            ?: mapOf(
-                ReactPopupMenuManager.REACT_CLASS to
-                    ModuleSpec.viewManagerSpec({ ReactPopupMenuManager() }))
-    viewManagersMap = viewManagers
-    return viewManagers
-  }
-
   protected override fun getViewManagers(context: ReactApplicationContext): List<ModuleSpec> {
-    return ArrayList(getViewManagersMap().values)
+    return viewManagersMap.values.toList()
   }
 
   override fun getViewManagerNames(context: ReactApplicationContext): Collection<String> {
-    return getViewManagersMap().keys
+    return viewManagersMap.keys
   }
 
   override fun createViewManager(
       reactContext: ReactApplicationContext,
       viewManagerName: String
   ): ViewManager<*, *>? {
-    val spec: ModuleSpec? = getViewManagersMap().get(viewManagerName)
+    val spec: ModuleSpec? = viewManagersMap.get(viewManagerName)
     return if (spec != null) (spec.getProvider().get() as ViewManager<*, *>) else null
   }