Add notification (and unit test) for closing prefs window so it can be cleane...

chrome/browser/app_controller_mac.mm

 // Copyright (c) 2009 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 "chrome/browser/app_controller_mac.h"
 
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/sys_string_conversions.h"
 #include "chrome/app/chrome_dll_resource.h"
@@ skipping 214 matching lines @@
     NSData* fileURLData = [fileURLDesc data];
     if (!fileURLData)
       continue;
     GURL gurl(std::string((char*)[fileURLData bytes], [fileURLData length]));
     gurlVector.push_back(gurl);
   }
 
   OpenURLs(gurlVector);
 }
 
+// Called when the preferences window is closed. We use this to release the
+// window controller.
+- (void)prefsWindowClosed:(NSNotification*)notify {
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  prefsController_.reset(NULL);
+}
+
 // Show the preferences window, or bring it to the front if it's already
 // visible.
 - (IBAction)showPreferences:(id)sender {
   if (!prefsController_.get()) {
     PrefService* prefs = [self defaultProfile]->GetPrefs();
     prefsController_.reset([[PreferencesWindowController alloc]
                               initWithPrefs:prefs]);
+    // Watch for a notification of when it goes away so that we can destroy
+    // the controller.
+    [[NSNotificationCenter defaultCenter]
+        addObserver:self
+           selector:@selector(prefsWindowClosed:)
+               name:kUserDoneEditingPrefsNotification
+             object:prefsController_.get()];
   }
   [prefsController_ showPreferences:sender];
 }
 
 @end