MacViews: Implement CloseNow() as just -[NSWindow close].

ui/views/widget/native_widget_mac.mm

 // Copyright 2014 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.
 
 #include "ui/views/widget/native_widget_mac.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include <utility>
 
@@ skipping 82 matching lines @@
     return [delegate nativeWidgetMac]->bridge_.get();
   }
   return nullptr;  // Not created by NativeWidgetMac.
 }
 
 bool NativeWidgetMac::IsWindowModalSheet() const {
   return GetWidget()->widget_delegate()->GetModalType() ==
          ui::MODAL_TYPE_WINDOW;
 }
 
-void NativeWidgetMac::OnWindowWillClose() {
-  // Note: If closed via CloseNow(), |bridge_| will already be reset. If closed
-  // by the user, or via Close() and a RunLoop, notify observers while |bridge_|
-  // is still a valid pointer, then reset it.
-  if (bridge_) {
-    delegate_->OnNativeWidgetDestroying();
-    [GetNativeWindow() setDelegate:nil];
-    bridge_.reset();
-  }
+void NativeWidgetMac::OnWindowDestroyed() {
+  DCHECK(bridge_);
+  bridge_.reset();
   delegate_->OnNativeWidgetDestroyed();
   if (ownership_ == Widget::InitParams::NATIVE_WIDGET_OWNS_WIDGET)
     delete this;
 }
 
 int NativeWidgetMac::SheetPositionY() {
   NSView* view = GetNativeView();
   return
       [view convertPoint:NSMakePoint(0, NSHeight([view frame])) toView:nil].y;
 }
@@ skipping 212 matching lines @@
 }
 
 void NativeWidgetMac::SetShape(std::unique_ptr<SkRegion> shape) {
   NOTIMPLEMENTED();
 }
 
 void NativeWidgetMac::Close() {
   if (!bridge_)
     return;
 
+  // Keep |window| on the stack so that the ObjectiveC block below can capture
+  // it and properly increment the reference count bound to the posted task.
   NSWindow* window = GetNativeWindow();
+
   if (IsWindowModalSheet()) {
     // Sheets can't be closed normally. This starts the sheet closing. Once the
     // sheet has finished animating, it will call sheetDidEnd: on the parent
     // window's delegate. Note it still needs to be asynchronous, since code
     // calling Widget::Close() doesn't expect things to be deleted upon return.
     [NSApp performSelector:@selector(endSheet:) withObject:window afterDelay:0];
     return;
   }
 
   // For other modal types, animate the close.
@@ skipping 17 matching lines @@
   // does not do this. So post a regular task.
   base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, base::BindBlock(^{
     [window close];
   }));
 }
 
 void NativeWidgetMac::CloseNow() {
   if (!bridge_)
     return;
 
-  // Notify observers while |bridged_| is still valid.
-  delegate_->OnNativeWidgetDestroying();
-  // Reset |bridge_| to NULL before destroying it.
-  std::unique_ptr<BridgedNativeWidget> bridge(std::move(bridge_));
+  // Cocoa ignores -close calls on open sheets, so they should be closed
+  // asynchronously, using Widget::Close().
+  DCHECK(!IsWindowModalSheet());
+
+  // NSWindows must be retained until -[NSWindow close] returns.
+  base::scoped_nsobject<NSWindow> window(GetNativeWindow(),
+                                         base::scoped_policy::RETAIN);
+
+  // If there's a bridge at this point, it means there must be a window as well.
+  DCHECK(window);
+  [window close];
+  // Note: |this| is deleted here when ownership_ == NATIVE_WIDGET_OWNS_WIDGET.
 }
 
 void NativeWidgetMac::Show() {
   ShowWithWindowState(ui::SHOW_STATE_NORMAL);
 }
 
 void NativeWidgetMac::Hide() {
   if (!bridge_)
     return;
 
@@ skipping 363 matching lines @@
   [[ViewsNSWindowCloseAnimator alloc] initWithWindow:window];
 }
 
 - (void)animationDidEnd:(NSAnimation*)animation {
   [window_ close];
   [animation_ setDelegate:nil];
   [self release];
 }
 
 @end