Remove remote JS debugging (iOS)

Summary:
## Context

**Remote JS Debugging removal**

In React Native 0.73, we have deprecated Remote JS Debugging (execution of JavaScript in a separate V8 process) and also removed the Dev Menu launcher (facebook#36754).

This was motivated primarily by the broken state of this feature — in particular: incompatibility with the New Architecture. Secondly, as the React Native team continues to invest in improving debugging, we want to reduce the surface area of debugging modes that we support.

During this year, we reached out to our partners about the impact of removing this feature, and if there was interest in having separate community support for debugging JSC on Android (a limited use case affected by this change). Without strong interest, we concluded that dropping Remote JS Debugging support in core for React Native 0.74 makes sense. We are focusing future debugging efforts into providing a first-class experience for Hermes.

Existing alternatives:

- [Direct debugging for JSC (Safari, iOS only)](https://reactnative.dev/docs/0.71/debugging#safari-developer-tools).
- Direct debugging with Hermes: Flipper, [Chrome (old method)](https://reactnative.dev/docs/0.71/hermes#debugging-js-on-hermes-using-google-chromes-devtools), or via `react-native start --experimental-debugger` (intended future default).

## This diff

This removes remaininng Remote JS Debugging code and `RCTWebSocketExecutor` on iOS.

Changelog: [iOS][Breaking] Remove remote JS debugging capability (JSC projects)

Differential Revision: D50326296

packages/react-native/React/CoreModules/CoreModulesPlugins.h

@@ -50,7 +50,6 @@ Class RCTRedBoxCls(void) __attribute__((used));
 Class RCTSourceCodeCls(void) __attribute__((used));
 Class RCTStatusBarManagerCls(void) __attribute__((used));
 Class RCTTimingCls(void) __attribute__((used));
-Class RCTWebSocketExecutorCls(void) __attribute__((used));
 Class RCTWebSocketModuleCls(void) __attribute__((used));
 Class RCTBlobManagerCls(void) __attribute__((used));
 

packages/react-native/React/CoreModules/CoreModulesPlugins.mm

@@ -40,7 +40,6 @@ Class RCTCoreModulesClassProvider(const char *name) {
     {"SourceCode", RCTSourceCodeCls},
     {"StatusBarManager", RCTStatusBarManagerCls},
     {"Timing", RCTTimingCls},
-    {"WebSocketExecutor", RCTWebSocketExecutorCls},
     {"WebSocketModule", RCTWebSocketModuleCls},
     {"BlobModule", RCTBlobManagerCls},
   };

packages/react-native/React/CoreModules/RCTDevSettings.h

@@ -47,7 +47,6 @@
 - (instancetype)initWithDataSource:(id<RCTDevSettingsDataSource>)dataSource;
 
 @property (nonatomic, readonly) BOOL isHotLoadingAvailable;
-@property (nonatomic, readonly) BOOL isRemoteDebuggingAvailable;
 @property (nonatomic, readonly) BOOL isDeviceDebuggingAvailable;
 @property (nonatomic, readonly) BOOL isJSCSamplingProfilerAvailable;
 

packages/react-native/React/CoreModules/RCTDevSettings.mm

@@ -176,37 +176,6 @@ - (instancetype)initWithDataSource:(id<RCTDevSettingsDataSource>)dataSource
 
 - (void)initialize
 {
-#if RCT_DEV_SETTINGS_ENABLE_PACKAGER_CONNECTION
-  if (self.bridge) {
-    RCTBridge *__weak weakBridge = self.bridge;
-    _bridgeExecutorOverrideToken = [[RCTPackagerConnection sharedPackagerConnection]
-        addNotificationHandler:^(id params) {
-          if (params != (id)kCFNull && [params[@"debug"] boolValue]) {
-            weakBridge.executorClass = objc_lookUpClass("RCTWebSocketExecutor");
-          }
-        }
-                         queue:dispatch_get_main_queue()
-                     forMethod:@"reload"];
-  }
-
-  if (numInitializedModules++ == 0) {
-    reloadToken = [[RCTPackagerConnection sharedPackagerConnection]
-        addNotificationHandler:^(id params) {
-          RCTTriggerReloadCommandListeners(@"Global hotkey");
-        }
-                         queue:dispatch_get_main_queue()
-                     forMethod:@"reload"];
-#if RCT_DEV_MENU
-    devMenuToken = [[RCTPackagerConnection sharedPackagerConnection]
-        addNotificationHandler:^(id params) {
-          [self.bridge.devMenu show];
-        }
-                         queue:dispatch_get_main_queue()
-                     forMethod:@"devMenu"];
-#endif
-  }
-#endif
-
 #if RCT_ENABLE_INSPECTOR
   if (self.bridge) {
     // We need this dispatch to the main thread because the bridge is not yet
@@ -290,15 +259,6 @@ - (BOOL)isDeviceDebuggingAvailable
 #endif // RCT_ENABLE_INSPECTOR
 }
 
-- (BOOL)isRemoteDebuggingAvailable
-{
-  if (RCTTurboModuleEnabled()) {
-    return NO;
-  }
-  Class jsDebuggingExecutorClass = objc_lookUpClass("RCTWebSocketExecutor");
-  return (jsDebuggingExecutorClass != nil);
-}
-
 - (BOOL)isHotLoadingAvailable
 {
   if (self.bundleManager.bundleURL) {
@@ -332,30 +292,6 @@ - (BOOL)isShakeToShowDevMenuEnabled
   return [[self settingForKey:kRCTDevSettingShakeToShowDevMenu] boolValue];
 }
 
-RCT_EXPORT_METHOD(setIsDebuggingRemotely : (BOOL)enabled)
-{
-  [self _updateSettingWithValue:@(enabled) forKey:kRCTDevSettingIsDebuggingRemotely];
-  [self _remoteDebugSettingDidChange];
-}
-
-- (BOOL)isDebuggingRemotely
-{
-  return [[self settingForKey:kRCTDevSettingIsDebuggingRemotely] boolValue];
-}
-
-- (void)_remoteDebugSettingDidChange
-{
-  // This value is passed as a command-line argument, so fall back to reading from NSUserDefaults directly
-  NSString *executorOverride = [[NSUserDefaults standardUserDefaults] stringForKey:kRCTDevSettingExecutorOverrideClass];
-  Class executorOverrideClass = executorOverride ? NSClassFromString(executorOverride) : nil;
-  if (executorOverrideClass) {
-    self.executorClass = executorOverrideClass;
-  } else {
-    BOOL enabled = self.isRemoteDebuggingAvailable && self.isDebuggingRemotely;
-    self.executorClass = enabled ? objc_getClass("RCTWebSocketExecutor") : nil;
-  }
-}
-
 RCT_EXPORT_METHOD(setProfilingEnabled : (BOOL)enabled)
 {
   [self _updateSettingWithValue:@(enabled) forKey:kRCTDevSettingProfilingEnabled];
@@ -450,11 +386,7 @@ - (void)setExecutorClass:(Class)executorClass
 {
   _executorClass = executorClass;
   if (self.bridge.executorClass != executorClass) {
-    // TODO (6929129): we can remove this special case test once we have better
-    // support for custom executors in the dev menu. But right now this is
-    // needed to prevent overriding a custom executor with the default if a
-    // custom executor has been set directly on the bridge
-    if (executorClass == Nil && self.bridge.executorClass != objc_lookUpClass("RCTWebSocketExecutor")) {
+    if (executorClass == Nil) {
       return;
     }
 
@@ -503,7 +435,6 @@ - (void)setupHMRClientWithAdditionalBundleURL:(NSURL *)bundleURL
  */
 - (void)_synchronizeAllSettings
 {
-  [self _remoteDebugSettingDidChange];
   [self _profilingSettingDidChange];
 }
 
@@ -563,10 +494,6 @@ - (BOOL)isHotLoadingAvailable
 {
   return NO;
 }
-- (BOOL)isRemoteDebuggingAvailable
-{
-  return NO;
-}
 + (BOOL)requiresMainQueueSetup
 {
   return NO;