Define continuous and idle priority for raw events and expose them to React via nativeFabricUIManager

packages/react-native/ReactAndroid/src/main/jni/react/fabric/FabricUIManagerBinding.cpp

@@ -10,7 +10,6 @@
 #include "AndroidEventBeat.h"
 #include "ComponentFactory.h"
 #include "EventBeatManager.h"
-#include "EventEmitterWrapper.h"
 #include "FabricMountingManager.h"
 
 #include <cxxreact/TraceSection.h>

packages/react-native/ReactCommon/react/renderer/core/EventQueueProcessor.cpp

@@ -55,6 +55,8 @@ void EventQueueProcessor::flushEvents(
             return ReactEventPriority::Discrete;
           case RawEvent::Category::Continuous:
             return ReactEventPriority::Continuous;
+          case RawEvent::Category::Idle:
+            return ReactEventPriority::Idle;
           case RawEvent::Category::Unspecified:
             return hasContinuousEventStarted_ ? ReactEventPriority::Continuous
                                               : ReactEventPriority::Default;

packages/react-native/ReactCommon/react/renderer/core/RawEvent.h

@@ -56,7 +56,13 @@ struct RawEvent {
      * Forces continuous type for the event. Regardless if continuous event
      * isn't ongoing.
      */
-    Continuous = 4
+    Continuous = 4,
+
+    /*
+     * Priority for events that can be processed in idle times or in the
+     * background.
+     */
+    Idle = 5,
   };
 
   RawEvent(

packages/react-native/ReactCommon/react/renderer/core/ReactEventPriority.h

@@ -30,6 +30,11 @@ enum class ReactEventPriority {
    * scrolling.
    */
   Continuous,
+
+  /*
+   * Other events that can be processed in the background.
+   */
+  Idle,
 };
 
 static constexpr std::underlying_type<ReactEventPriority>::type serialize(

packages/react-native/ReactCommon/react/renderer/uimanager/UIManagerBinding.cpp

@@ -747,6 +747,14 @@ jsi::Value UIManagerBinding::get(
     return {serialize(ReactEventPriority::Discrete)};
   }
 
+  if (methodName == "unstable_ContinuousEventPriority") {
+    return {serialize(ReactEventPriority::Continuous)};
+  }
+
+  if (methodName == "unstable_IdleEventPriority") {
+    return {serialize(ReactEventPriority::Idle)};
+  }
+
   if (methodName == "findShadowNodeByTag_DEPRECATED") {
     auto paramCount = 1;
     return jsi::Function::createFromHostFunction(