revert: remove macOS traffic light adjustments

ui/flutter/macos/Runner/MainFlutterWindow.swift

@@ -4,12 +4,6 @@ import desktop_multi_window
 import window_manager
 
 class MainFlutterWindow: NSWindow {
-  // Keep this in sync with AppDesignTokens.railWidth in Flutter.
-  private static let navigationRailWidth: CGFloat = 68
-  private static let trafficLightGap: CGFloat = 6
-  private var trafficLightLayoutScheduled = false
-  private var fullScreenTransitionInProgress = false
-
   override func awakeFromNib() {
     let flutterViewController = FlutterViewController()
     let windowFrame = self.frame
@@ -22,83 +16,10 @@ class MainFlutterWindow: NSWindow {
     }
 
     super.awakeFromNib()
-
-    for name in [NSWindow.didResizeNotification, NSWindow.didBecomeKeyNotification,
-                 NSWindow.didChangeBackingPropertiesNotification] {
-      NotificationCenter.default.addObserver(
-        self, selector: #selector(refreshTrafficLightLayout(_:)), name: name, object: self)
-    }
-    for name in [NSWindow.willEnterFullScreenNotification, NSWindow.willExitFullScreenNotification] {
-      NotificationCenter.default.addObserver(
-        self, selector: #selector(beginFullScreenTransition(_:)), name: name, object: self)
-    }
-    for name in [NSWindow.didEnterFullScreenNotification, NSWindow.didExitFullScreenNotification] {
-      NotificationCenter.default.addObserver(
-        self, selector: #selector(endFullScreenTransition(_:)), name: name, object: self)
-    }
-    scheduleTrafficLightLayout()
-  }
-
-  private func positionTrafficLights() {
-    // Let AppKit position controls in its own full-screen title bar.
-    guard !styleMask.contains(.fullScreen) else { return }
-
-    let buttons = [NSWindow.ButtonType.closeButton, .miniaturizeButton, .zoomButton]
-      .compactMap { standardWindowButton($0) }
-    guard buttons.count == 3 else { return }
-
-    let width = buttons.reduce(CGFloat.zero) { $0 + $1.frame.width }
-      + Self.trafficLightGap * CGFloat(buttons.count - 1)
-    var x = (Self.navigationRailWidth - width) / 2
-    guard x >= 0 else { return }
-
-    // Keep native sizes, vertical positions and button behavior intact.
-    for button in buttons {
-      var origin = button.frame.origin
-      origin.x = x
-      if button.frame.origin != origin {
-        button.setFrameOrigin(origin)
-      }
-      x += button.frame.width + Self.trafficLightGap
-    }
-  }
-
-  @objc private func refreshTrafficLightLayout(_ notification: Notification) {
-    scheduleTrafficLightLayout()
-  }
-
-  @objc private func beginFullScreenTransition(_ notification: Notification) {
-    fullScreenTransitionInProgress = true
-  }
-
-  @objc private func endFullScreenTransition(_ notification: Notification) {
-    fullScreenTransitionInProgress = false
-    scheduleTrafficLightLayout()
-  }
-
-  private func scheduleTrafficLightLayout() {
-    guard !trafficLightLayoutScheduled else { return }
-    trafficLightLayoutScheduled = true
-    // AppKit can reset button frames while finishing a resize or style change.
-    DispatchQueue.main.async { [weak self] in
-      guard let self = self else { return }
-      self.trafficLightLayoutScheduled = false
-      guard !self.fullScreenTransitionInProgress, !self.styleMask.contains(.fullScreen) else { return }
-      // Calling this is supported; overriding AppKit's layout entry point is not.
-      self.layoutIfNeeded()
-      self.positionTrafficLights()
-    }
-  }
-
-  deinit {
-    NotificationCenter.default.removeObserver(self)
   }
 
   override public func order(_ place: NSWindow.OrderingMode, relativeTo otherWin: Int) {
     super.order(place, relativeTo: otherWin)
     hiddenWindowAtLaunch()
-    if place == .above {
-      scheduleTrafficLightLayout()
-    }
   }
 }