Remove unused microtask methods (#54435)

Summary:
Pull Request resolved: #54435

We rely on the JS VM to provide a fully functional microtask queue, and this is no longer used.

Changelog: [General][Breaking] Removed microtask API from JSTimerManager

Reviewed By: mdvacca

Differential Revision: D86420043

fbshipit-source-id: d8d08c4cbbb001504e533c4b730fdf95561c04a5

Author: javache

packages/react-native/ReactCommon/react/runtime/TimerManager.cpp

@@ -8,7 +8,6 @@
 #include "TimerManager.h"
 
 #include <cxxreact/TraceSection.h>
-#include <react/featureflags/ReactNativeFeatureFlags.h>
 
 #include <cmath>
 #include <utility>
@@ -62,41 +61,6 @@ void TimerManager::setRuntimeExecutor(
   runtimeExecutor_ = std::move(runtimeExecutor);
 }
 
-TimerHandle TimerManager::createReactNativeMicrotask(
-    jsi::Function&& callback,
-    std::vector<jsi::Value>&& args) {
-  // Get the id for the callback.
-  TimerHandle timerID = timerIndex_++;
-  timers_.emplace(
-      std::piecewise_construct,
-      std::forward_as_tuple(timerID),
-      std::forward_as_tuple(
-          std::move(callback), std::move(args), /* repeat */ false));
-
-  reactNativeMicrotasksQueue_.push_back(timerID);
-  return timerID;
-}
-
-void TimerManager::callReactNativeMicrotasks(jsi::Runtime& runtime) {
-  std::vector<TimerHandle> reactNativeMicrotasksQueue;
-  while (!reactNativeMicrotasksQueue_.empty()) {
-    reactNativeMicrotasksQueue.clear();
-    reactNativeMicrotasksQueue.swap(reactNativeMicrotasksQueue_);
-
-    for (auto reactNativeMicrotaskID : reactNativeMicrotasksQueue) {
-      // ReactNativeMicrotasks can clear other scheduled reactNativeMicrotasks.
-      auto it = timers_.find(reactNativeMicrotaskID);
-      if (it != timers_.end()) {
-        it->second.invoke(runtime);
-
-        // Invoking a timer has the potential to delete it. Do not re-use the
-        // existing iterator to erase it from the map.
-        timers_.erase(reactNativeMicrotaskID);
-      }
-    }
-  }
-}
-
 TimerHandle TimerManager::createTimer(
     jsi::Function&& callback,
     std::vector<jsi::Value>&& args,
@@ -156,24 +120,6 @@ TimerHandle TimerManager::createRecurringTimer(
   return timerID;
 }
 
-void TimerManager::deleteReactNativeMicrotask(
-    jsi::Runtime& runtime,
-    TimerHandle timerHandle) {
-  if (timerHandle < 0) {
-    throw jsi::JSError(
-        runtime, "clearReactNativeMicrotask was called with an invalid handle");
-  }
-
-  auto it = std::find(
-      reactNativeMicrotasksQueue_.begin(),
-      reactNativeMicrotasksQueue_.end(),
-      timerHandle);
-  if (it != reactNativeMicrotasksQueue_.end()) {
-    reactNativeMicrotasksQueue_.erase(it);
-    timers_.erase(timerHandle);
-  }
-}
-
 void TimerManager::deleteTimer(jsi::Runtime& runtime, TimerHandle timerHandle) {
   if (timerHandle < 0) {
     throw jsi::JSError(runtime, "clearTimeout called with an invalid handle");

packages/react-native/ReactCommon/react/runtime/TimerManager.h

@@ -8,7 +8,6 @@
 #pragma once
 
 #include <ReactCommon/RuntimeExecutor.h>
-#include <cstdint>
 #include <unordered_map>
 #include <vector>
 
@@ -50,17 +49,11 @@ class TimerManager {
 
   void setRuntimeExecutor(RuntimeExecutor runtimeExecutor) noexcept;
 
-  void callReactNativeMicrotasks(jsi::Runtime &runtime);
-
   void callTimer(TimerHandle handle);
 
   void attachGlobals(jsi::Runtime &runtime);
 
  private:
-  TimerHandle createReactNativeMicrotask(jsi::Function &&callback, std::vector<jsi::Value> &&args);
-
-  void deleteReactNativeMicrotask(jsi::Runtime &runtime, TimerHandle handle);
-
   TimerHandle createTimer(
       jsi::Function &&callback,
       std::vector<jsi::Value> &&args,
@@ -88,11 +81,6 @@ class TimerManager {
   // As per WHATWG HTML 8.6.1 (Timers) ids must be greater than zero, i.e. start
   // at 1
   TimerHandle timerIndex_{1};
-
-  // The React Native microtask queue is used to back public APIs including
-  // `queueMicrotask`, `clearImmediate`, and `setImmediate` (which is used by
-  // the Promise polyfill) when the JSVM microtask mechanism is not used.
-  std::vector<TimerHandle> reactNativeMicrotasksQueue_;
 };
 
 } // namespace facebook::react