[Mac] In BrowserWindowCocoa::Close() do not use -[NSWindow performClose:].

chrome/browser/ui/cocoa/browser_window_cocoa.mm

Index: chrome/browser/ui/cocoa/browser_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_cocoa.mm b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
index 31116d4f1b1a3370dfabfe9c0bca767f58a50207..91d9c00c04011a9d300eaa10c7deb54878e43a1d 100644
--- a/chrome/browser/ui/cocoa/browser_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
@@ -170,7 +170,22 @@ void BrowserWindowCocoa::Close() {
   if ([controller_ overlayWindow]) {
     [controller_ deferPerformClose];
   } else {
-    [window() performClose:controller_];
+    // Using |-performClose:| can prevent the window from actually closing if
+    // a JavaScript beforeunload handler opens an alert during shutdown, as
+    // documented at <http://crbug.com/118424>. Re-implement
+    // -[NSWindow performClose:] as closely as possible to how Apple documents
+    // it.
+    id<NSWindowDelegate> delegate = [window() delegate];
+    SEL windowShouldClose = @selector(windowShouldClose:);

[Mark Mentovai, 2012/10/11 15:44:57]

window_should_close

[Robert Sesek, 2012/10/11 15:58:39]

Done.

+    if ([delegate respondsToSelector:windowShouldClose]) {
+      if ([delegate windowShouldClose:window()])
+        [window() close];
+    } else if ([window() respondsToSelector:windowShouldClose]) {
+      if ([window() performSelector:windowShouldClose withObject:window()])

[Mark Mentovai, 2012/10/11 15:44:57]

Why not just [window windowShouldClose:window()]?

Or if you want to use -performSelector, why didn’t you use it when calling the
delegate?

[Robert Sesek, 2012/10/11 15:58:39]

NSWindow does implement windowShouldClose: and it's not in its interface. That's
why the test needs a fake one.

[Mark Mentovai, 2012/10/11 16:04:03]

Oh yeah, duh, your comment even said that.

+        [window() close];
+    } else {
+      [window() close];
+    }
   }
 }