Fix possible deadlock in dispatchViewUpdates (#43643)

Summary:
In https://github.com/th3rdwave/react-native-safe-area-context/issues/448 it was noticed that from 0.72 (https://github.com/facebook/react-native/commit/bc766ec7f8b18ddc0ff72a2fff5783eeeff24857 https://github.com/facebook/react-native/pull/35889) it was possible to get a deadlock in dispatchViewUpdates. ([More details](https://github.com/th3rdwave/react-native-safe-area-context/issues/448#issuecomment-1871155936))

This deadlock resulted in a laggy experience for all users using https://github.com/th3rdwave/react-native-safe-area-context/ on Android.

To avoid this problem, the author of the original fix [proposed](https://github.com/th3rdwave/react-native-safe-area-context/issues/448#issuecomment-1872121172) this solution which was tested by Discord and many other users.

It would be great to have this backported to 0.72 and 0.73 because of the large userbase using react-native-safe-area-context since it's recommended by expo and react-navigation.

## Changelog:

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[ANDROID] [FIXED] - Fixed possible deadlock in dispatchViewUpdates

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[ANDROID] [FIXED] - Fixed possible deadlock in dispatchViewUpdates

Pull Request resolved: https://github.com/facebook/react-native/pull/43643

Test Plan:
The original memory leak remains fixed, and can be verified in https://github.com/feiyin0719/RNMemoryLeakAndroid.

To verify the deadlock is gone, every app using https://github.com/th3rdwave/react-native-safe-area-context will work smoothly and not log any excessive `Timed out waiting for layout`
(https://github.com/17Amir17/SafeAreaContext)

Reviewed By: arushikesarwani94

Differential Revision: D55339059

Pulled By: zeyap

fbshipit-source-id: c067997364fbec734510ce99b9994e89d044384a

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

@@ -4892,6 +4892,7 @@ public class com/facebook/react/uimanager/UIImplementation {
 	public fun dispatchViewUpdates (I)V
 	public fun findSubviewIn (IFFLcom/facebook/react/bridge/Callback;)V
 	public fun getProfiledBatchPerfCounters ()Ljava/util/Map;
+	public fun getRootViewNum ()I
 	protected fun handleCreateView (Lcom/facebook/react/uimanager/ReactShadowNode;ILcom/facebook/react/uimanager/ReactStylesDiffMap;)V
 	protected fun handleUpdateView (Lcom/facebook/react/uimanager/ReactShadowNode;Ljava/lang/String;Lcom/facebook/react/uimanager/ReactStylesDiffMap;)V
 	public fun manageChildren (ILcom/facebook/react/bridge/ReadableArray;Lcom/facebook/react/bridge/ReadableArray;Lcom/facebook/react/bridge/ReadableArray;Lcom/facebook/react/bridge/ReadableArray;Lcom/facebook/react/bridge/ReadableArray;)V

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

@@ -177,7 +177,7 @@ public class UIImplementation {
    *
    * @return The num of root view
    */
-  private int getRootViewNum() {
+  public int getRootViewNum() {
     return mOperationsQueue.getNativeViewHierarchyManager().getRootViewNum();
   }
 
@@ -589,12 +589,6 @@ public class UIImplementation {
 
   /** Invoked at the end of the transaction to commit any updates to the node hierarchy. */
   public void dispatchViewUpdates(int batchId) {
-    if (getRootViewNum() <= 0) {
-      // If there are no RootViews registered, there will be no View updates to dispatch.
-      // This is a hack to prevent this from being called when Fabric is used everywhere.
-      // This should no longer be necessary in Bridgeless Mode.
-      return;
-    }
     SystraceMessage.beginSection(
             Systrace.TRACE_TAG_REACT_JAVA_BRIDGE, "UIImplementation.dispatchViewUpdates")
         .arg("batchId", batchId)

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

@@ -707,7 +707,12 @@ public class UIManagerModule extends ReactContextBaseJavaModule
       listener.willDispatchViewUpdates(this);
     }
     try {
-      mUIImplementation.dispatchViewUpdates(batchId);
+      // If there are no RootViews registered, there will be no View updates to dispatch.
+      // This is a hack to prevent this from being called when Fabric is used everywhere.
+      // This should no longer be necessary in Bridgeless Mode.
+      if (mUIImplementation.getRootViewNum() > 0) {
+        mUIImplementation.dispatchViewUpdates(batchId);
+      }
     } finally {
       Systrace.endSection(Systrace.TRACE_TAG_REACT_JAVA_BRIDGE);
     }