MacViews: Suppress visibility changes during an asynchronous close.

ui/views/cocoa/views_nswindow_close_animator.mm

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ui/views/cocoa/views_nswindow_close_animator.h"
+
+#import <AppKit/AppKit.h>
+
+#import "ui/base/cocoa/constrained_window/constrained_window_animation.h"
+
+@interface ViewsNSWindowCloseAnimator : NSObject<NSAnimationDelegate>
+- (id)initWithWindow:(NSWindow*)window;
+@end
+
+namespace views {
+
+void CloseNativeWindowWithAnimation(NSWindow* window) {
+  [[ViewsNSWindowCloseAnimator alloc] initWithWindow:window];
+}
+
+}  // namespace views
+
+@implementation ViewsNSWindowCloseAnimator {
+ @private
+  base::scoped_nsobject<NSWindow> window_;
+  base::scoped_nsobject<NSAnimation> animation_;
+}
+
+- (id)initWithWindow:(NSWindow*)window {
+  if ((self = [super init])) {
+    window_.reset([window retain]);
+    animation_.reset(
+        [[ConstrainedWindowAnimationHide alloc] initWithWindow:window]);
+    [animation_ setDelegate:self];
+    [animation_ setAnimationBlockingMode:NSAnimationNonblocking];
+    [animation_ startAnimation];
+  }
+  return self;
+}
+
+- (void)animationDidEnd:(NSAnimation*)animation {
+  [window_ close];
+  [animation_ setDelegate:nil];
+  [self release];
+}
+
+@end