Expose lazyViewManagers option on ReactNativeHost

Summary: Changelog: [Android][Added] Option to enable lazyViewManager support with `ViewManagerOnDemandReactPackage`

Reviewed By: RSNara

Differential Revision: D36130066

fbshipit-source-id: b8b04b46f59248baacdf1717f7e32b45e56dd2b8

ReactAndroid/src/main/java/com/facebook/react/ReactNativeHost.java

@@ -74,6 +74,7 @@ public abstract class ReactNativeHost {
             .setDevSupportManagerFactory(getDevSupportManagerFactory())
             .setRequireActivity(getShouldRequireActivity())
             .setSurfaceDelegateFactory(getSurfaceDelegateFactory())
+            .setLazyViewManagersEnabled(getLazyViewManagersEnabled())
             .setRedBoxHandler(getRedBoxHandler())
             .setJavaScriptExecutorFactory(getJavaScriptExecutorFactory())
             .setUIImplementationProvider(getUIImplementationProvider())
@@ -135,6 +136,16 @@ public abstract class ReactNativeHost {
     return true;
   }
 
+  /**
+   * Returns whether view managers should be created lazily. See {@link
+   * ViewManagerOnDemandReactPackage} for details.
+   *
+   * @experimental
+   */
+  public boolean getLazyViewManagersEnabled() {
+    return false;
+  }
+
   /**
    * Return the {@link SurfaceDelegateFactory} used by NativeModules to get access to a {@link
    * SurfaceDelegate} to interact with a surface. By default in the mobile platform the {@link