Migrate ReactRoot to Kotlin (#53238)

Summary:
Pull Request resolved: #53238

Changelog:
[Android][Changed] - Migrated ReactRoot to Kotlin

Reviewed By: cortinico

Differential Revision: D80074359

fbshipit-source-id: 273f5bfc2826f59f2bb1521b8dbd95c48e5eb0c4

Author: sbuggay

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -3806,6 +3806,7 @@ public abstract interface class com/facebook/react/uimanager/ReactPointerEventsV
 }
 
 public abstract interface class com/facebook/react/uimanager/ReactRoot {
+	public static final field Companion Lcom/facebook/react/uimanager/ReactRoot$Companion;
 	public static final field STATE_STARTED I
 	public static final field STATE_STOPPED I
 	public abstract fun getAppProperties ()Landroid/os/Bundle;
@@ -3823,6 +3824,11 @@ public abstract interface class com/facebook/react/uimanager/ReactRoot {
 	public abstract fun setShouldLogContentAppeared (Z)V
 }
 
+public final class com/facebook/react/uimanager/ReactRoot$Companion {
+	public static final field STATE_STARTED I
+	public static final field STATE_STOPPED I
+}
+
 public abstract interface class com/facebook/react/uimanager/ReactShadowNode {
 	public abstract fun addChildAt (Lcom/facebook/react/uimanager/ReactShadowNode;I)V
 	public abstract fun addNativeChildAt (Lcom/facebook/react/uimanager/ReactShadowNode;I)V

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactRoot.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.uimanager
+
+import android.os.Bundle
+import android.view.ViewGroup
+import com.facebook.react.uimanager.common.UIManagerType
+import java.util.concurrent.atomic.AtomicInteger
+
+/** Interface for the root native view of a React native application */
+public interface ReactRoot {
+
+  public companion object {
+    /** This constant represents that ReactRoot hasn't started yet or it has been destroyed. */
+    public const val STATE_STOPPED: Int = 0
+
+    /** This constant represents that ReactRoot has started. */
+    public const val STATE_STARTED: Int = 1
+  }
+
+  /** Return cached launch properties for app */
+  public fun getAppProperties(): Bundle?
+
+  public fun getJSModuleName(): String
+
+  /** Fabric or Default UI Manager, see [UIManagerType] */
+  @UIManagerType public fun getUIManagerType(): Int
+
+  public fun getRootViewTag(): Int
+
+  public fun setRootViewTag(rootViewTag: Int)
+
+  /** Calls into JS to start the React application. */
+  public fun runApplication()
+
+  /** Handler for stages [com.facebook.react.surface.ReactStage] */
+  public fun onStage(@ReactStage stage: Int)
+
+  /** Return native view for root */
+  public fun getRootViewGroup(): ViewGroup
+
+  /** @return Cached values for widthMeasureSpec. */
+  public fun getWidthMeasureSpec(): Int
+
+  /** @return Cached values for and heightMeasureSpec. */
+  public fun getHeightMeasureSpec(): Int
+
+  /** Sets a flag that determines whether to log that content appeared on next view added. */
+  public fun setShouldLogContentAppeared(shouldLogContentAppeared: Boolean)
+
+  /**
+   * @return a [String] that represents the root js application that is being rendered with this
+   *   [ReactRoot]
+   * @deprecated We recommend to not use this method as it is will be replaced in the near future.
+   */
+  @Deprecated("We recommend to not use this method as it is will be replaced in the near future.")
+  public fun getSurfaceID(): String?
+
+  /** @return an [AtomicInteger] that represents the state of the ReactRoot object. */
+  public fun getState(): AtomicInteger
+}

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

@@ -194,7 +194,8 @@ public object UIManagerHelper {
   public fun getSurfaceId(view: View): Int {
     if (view is ReactRoot) {
       val rootView = view as ReactRoot
-      return if (rootView.uiManagerType == UIManagerType.FABRIC) rootView.rootViewTag else -1
+      return if (rootView.getUIManagerType() == UIManagerType.FABRIC) rootView.getRootViewTag()
+      else -1
     }
 
     val reactTag = view.id

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

@@ -98,7 +98,7 @@ class RootViewTest {
     val rootViewId = 11
     val rootView = ReactRootView(reactContext)
     rootView.id = rootViewId
-    rootView.rootViewTag = rootViewId
+    rootView.setRootViewTag(rootViewId)
     rootView.startReactApplication(instanceManager, "")
     rootView.simulateAttachForTesting()
     val ts = SystemClock.currentTimeMillis()