Remove feature flag for layout transition tag cleanup

Summary:
Removes stale feature flag that was in production for a couple of months. Fix helped to decrease number of crashes significantly, so we can remove it.

Changelog: [Internal]

Reviewed By: mdvacca

Differential Revision: D28757995

fbshipit-source-id: 375da09c11f265e8bbe03cd99de1b83f168420ce

Author: Andrei Shikov

ReactAndroid/src/main/java/com/facebook/react/config/ReactFeatureFlags.java

@@ -44,12 +44,6 @@ public interface FlagProvider {
   /** This feature flag enables logs for Fabric */
   public static boolean enableFabricLogs = false;
 
-  /**
-   * Temporary feature flat to control a fix in the transition to layoutOnlyViews TODO T61185028:
-   * remove this when bug is fixed
-   */
-  public static boolean enableTransitionLayoutOnlyViewCleanup = false;
-
   /** Feature flag to configure eager initialization of Fabric */
   public static boolean eagerInitializeFabric = false;
 

ReactAndroid/src/main/java/com/facebook/react/uimanager/NativeViewHierarchyOptimizer.java

@@ -13,7 +13,6 @@
 import com.facebook.infer.annotation.Assertions;
 import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.bridge.ReadableMapKeySetIterator;
-import com.facebook.react.config.ReactFeatureFlags;
 
 /**
  * Class responsible for optimizing the native view hierarchy while still respecting the final UI
@@ -425,18 +424,16 @@ private void transitionLayoutOnlyViewToNativeView(
     // Bit of a hack: we need to update the layout of this node's children now that it's no longer
     // layout-only, but we may still receive more layout updates at the end of this batch that we
     // don't want to ignore.
-    if (ReactFeatureFlags.enableTransitionLayoutOnlyViewCleanup) {
-      FLog.i(
-          TAG,
-          "Transitioning LayoutOnlyView - tag: "
-              + node.getReactTag()
-              + " - rootTag: "
-              + node.getRootTag()
-              + " - hasProps: "
-              + (props != null)
-              + " - tagsWithLayout.size: "
-              + mTagsWithLayoutVisited.size());
-    }
+    FLog.i(
+        TAG,
+        "Transitioning LayoutOnlyView - tag: "
+            + node.getReactTag()
+            + " - rootTag: "
+            + node.getRootTag()
+            + " - hasProps: "
+            + (props != null)
+            + " - tagsWithLayout.size: "
+            + mTagsWithLayoutVisited.size());
     Assertions.assertCondition(mTagsWithLayoutVisited.size() == 0);
     applyLayoutBase(node);
     for (int i = 0; i < node.getChildCount(); i++) {

ReactAndroid/src/main/java/com/facebook/react/uimanager/UIImplementation.java

@@ -21,7 +21,6 @@
 import com.facebook.react.bridge.UiThreadUtil;
 import com.facebook.react.bridge.WritableArray;
 import com.facebook.react.common.ReactConstants;
-import com.facebook.react.config.ReactFeatureFlags;
 import com.facebook.react.modules.i18nmanager.I18nUtil;
 import com.facebook.react.uimanager.debug.NotThreadSafeViewHierarchyUpdateDebugListener;
 import com.facebook.react.uimanager.events.EventDispatcher;
@@ -965,9 +964,7 @@ protected void applyUpdatesRecursive(ReactShadowNode cssNode, float absoluteX, f
       }
     }
     cssNode.markUpdateSeen();
-    if (ReactFeatureFlags.enableTransitionLayoutOnlyViewCleanup) {
-      mNativeViewHierarchyOptimizer.onViewUpdatesCompleted(cssNode);
-    }
+    mNativeViewHierarchyOptimizer.onViewUpdatesCompleted(cssNode);
   }
 
   public void addUIBlock(UIBlock block) {