Kotlinify SimpleViewManager (#43834)

Summary:
Pull Request resolved: #43834

Changelog: [Internal]

As part of the Sustainability Week (see [post](https://fb.workplace.com/groups/251759413609061/permalink/742797531171911/)).

Reviewed By: cortinico

Differential Revision: D55708429

fbshipit-source-id: ff76e5dc2e8c6d99b7792ed58e8bcd5e1441b2dd

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/SimpleViewManager.java → packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/SimpleViewManager.kt

@@ -5,10 +5,9 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-package com.facebook.react.uimanager;
+package com.facebook.react.uimanager
 
-import android.view.View;
-import com.facebook.infer.annotation.Nullsafe;
+import android.view.View
 
 /**
  * Common base class for most of the {@link ViewManager}s. It provides support for most common
@@ -18,20 +17,15 @@
  *
  * @param <T> the view handled by this manager
  */
-@Nullsafe(Nullsafe.Mode.LOCAL)
-public abstract class SimpleViewManager<T extends View>
-    extends BaseViewManager<T, LayoutShadowNode> {
+public abstract class SimpleViewManager<T : View> : BaseViewManager<T, LayoutShadowNode>() {
 
-  @Override
-  public LayoutShadowNode createShadowNodeInstance() {
-    return new LayoutShadowNode();
+  override public fun createShadowNodeInstance(): LayoutShadowNode {
+    return LayoutShadowNode()
   }
 
-  @Override
-  public Class<LayoutShadowNode> getShadowNodeClass() {
-    return LayoutShadowNode.class;
+  override public fun getShadowNodeClass(): Class<LayoutShadowNode> {
+    return LayoutShadowNode::class.java
   }
 
-  @Override
-  public void updateExtraData(T root, Object extraData) {}
+  override public fun updateExtraData(root: T, extraData: Any?): Unit = Unit
 }

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/uimanager/SimpleViewPropertyTest.kt

@@ -27,7 +27,7 @@ import org.robolectric.RuntimeEnvironment
 @RunWith(RobolectricTestRunner::class)
 class SimpleViewPropertyTest {
 
-  private class ConcreteViewManager : SimpleViewManager<View?>() {
+  private class ConcreteViewManager : SimpleViewManager<View>() {
     @Suppress("UNUSED_PARAMETER")
     @ReactProp(name = "foo")
     fun setFoo(view: View, foo: Boolean) = Unit