Remove delay between instance start and surface creation

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlags.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<3fa1a97be20aa80ef7a1e1595bee0dac>>
+ * @generated SignedSource<<687c29d850df9a857749d06c54cbddb7>>
  */
 
 /**
@@ -58,6 +58,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun changeOrderOfMountingInstructionsOnAndroid(): Boolean = accessor.changeOrderOfMountingInstructionsOnAndroid()
 
+  /**
+   * Do not wait for a main-thread dispatch to complete init to start executing work on the JS thread on Android
+   */
+  @JvmStatic
+  public fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean = accessor.completeReactInstanceCreationOnBgThreadOnAndroid()
+
   /**
    * When enabled, ReactInstanceManager will clean up Fabric surfaces on destroy().
    */

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<89b4a679d8121ece9291dd55c46567ad>>
+ * @generated SignedSource<<a80c0d6190fe0222bfdd4a39d7116908>>
  */
 
 /**
@@ -25,6 +25,7 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
   private var allowRecursiveCommitsWithSynchronousMountOnAndroidCache: Boolean? = null
   private var batchRenderingUpdatesInEventLoopCache: Boolean? = null
   private var changeOrderOfMountingInstructionsOnAndroidCache: Boolean? = null
+  private var completeReactInstanceCreationOnBgThreadOnAndroidCache: Boolean? = null
   private var destroyFabricSurfacesInReactInstanceManagerCache: Boolean? = null
   private var enableAlignItemsBaselineOnFabricIOSCache: Boolean? = null
   private var enableCleanTextInputYogaNodeCache: Boolean? = null
@@ -98,6 +99,15 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
     return cached
   }
 
+  override fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean {
+    var cached = completeReactInstanceCreationOnBgThreadOnAndroidCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.completeReactInstanceCreationOnBgThreadOnAndroid()
+      completeReactInstanceCreationOnBgThreadOnAndroidCache = cached
+    }
+    return cached
+  }
+
   override fun destroyFabricSurfacesInReactInstanceManager(): Boolean {
     var cached = destroyFabricSurfacesInReactInstanceManagerCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxInterop.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<98bd8f4b2b262ac3e75897da515706f5>>
+ * @generated SignedSource<<af43467b1d1c4cd6d1f42a597a791899>>
  */
 
 /**
@@ -38,6 +38,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun changeOrderOfMountingInstructionsOnAndroid(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean
+
   @DoNotStrip @JvmStatic public external fun destroyFabricSurfacesInReactInstanceManager(): Boolean
 
   @DoNotStrip @JvmStatic public external fun enableAlignItemsBaselineOnFabricIOS(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<a42ecd51ef7f12eb8758dbd029a2d67b>>
+ * @generated SignedSource<<8903d3fb0088fcdd9ac3e789299b8b6c>>
  */
 
 /**
@@ -33,6 +33,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun changeOrderOfMountingInstructionsOnAndroid(): Boolean = false
 
+  override fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean = false
+
   override fun destroyFabricSurfacesInReactInstanceManager(): Boolean = false
 
   override fun enableAlignItemsBaselineOnFabricIOS(): Boolean = true

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsLocalAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<96ed168a0e80e78d1d6f96374f045eca>>
+ * @generated SignedSource<<bf73788f1e8314232f880108b8a7c671>>
  */
 
 /**
@@ -29,6 +29,7 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
   private var allowRecursiveCommitsWithSynchronousMountOnAndroidCache: Boolean? = null
   private var batchRenderingUpdatesInEventLoopCache: Boolean? = null
   private var changeOrderOfMountingInstructionsOnAndroidCache: Boolean? = null
+  private var completeReactInstanceCreationOnBgThreadOnAndroidCache: Boolean? = null
   private var destroyFabricSurfacesInReactInstanceManagerCache: Boolean? = null
   private var enableAlignItemsBaselineOnFabricIOSCache: Boolean? = null
   private var enableCleanTextInputYogaNodeCache: Boolean? = null
@@ -107,6 +108,16 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean {
+    var cached = completeReactInstanceCreationOnBgThreadOnAndroidCache
+    if (cached == null) {
+      cached = currentProvider.completeReactInstanceCreationOnBgThreadOnAndroid()
+      accessedFeatureFlags.add("completeReactInstanceCreationOnBgThreadOnAndroid")
+      completeReactInstanceCreationOnBgThreadOnAndroidCache = cached
+    }
+    return cached
+  }
+
   override fun destroyFabricSurfacesInReactInstanceManager(): Boolean {
     var cached = destroyFabricSurfacesInReactInstanceManagerCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsProvider.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<13469640e36f5985531f872b28ff0c30>>
+ * @generated SignedSource<<0284ff2541a06bfa36bb7049d47cb4d2>>
  */
 
 /**
@@ -33,6 +33,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun changeOrderOfMountingInstructionsOnAndroid(): Boolean
 
+  @DoNotStrip public fun completeReactInstanceCreationOnBgThreadOnAndroid(): Boolean
+
   @DoNotStrip public fun destroyFabricSurfacesInReactInstanceManager(): Boolean
 
   @DoNotStrip public fun enableAlignItemsBaselineOnFabricIOS(): Boolean