[Mac] Polish the search engine manager

chrome/browser/cocoa/preferences_window_controller.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/cocoa/preferences_window_controller.h"
 
 #include "app/l10n_util.h"
 #include "base/mac_util.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
@@ skipping 522 matching lines @@
   [self recordUserAction:L"Options_SearchEngineChanged"];
   [searchEngineModel_ setDefaultIndex:index];
 }
 
 // Called when the search engine model changes. Update the selection in the
 // popup by tickling the bindings with the new value.
 - (void)searchEngineModelChanged:(NSNotification*)notify {
   [self setSearchEngineSelectedIndex:[self searchEngineSelectedIndex]];
 }
 
+// Notification receiver for when the keyword editor window closes. The
+// controller will clean up the window, but we need to clean up.
+- (void)keywordEditorClosed:(NSNotification*)notif {
+  keywordEditorController_ = nil;
+}
+
 // Brings up the edit search engines window.
 - (IBAction)manageSearchEngines:(id)sender {
-  KeywordEditorCocoaController* controller =
-      [[KeywordEditorCocoaController alloc] initWithProfile:profile_];
-  [[controller window] makeKeyAndOrderFront:sender];
+  if (!keywordEditorController_) {
+    keywordEditorController_ =
+        [[KeywordEditorCocoaController alloc] initWithProfile:profile_];
+    NSNotificationCenter* center = [NSNotificationCenter defaultCenter];
+    [center addObserver:self
+               selector:@selector(keywordEditorClosed:)
+                   name:NSWindowWillCloseNotification
+                 object:[keywordEditorController_ window]];
+  }
+  [[keywordEditorController_ window] makeKeyAndOrderFront:sender];
 }
 
 // Called when the user clicks the button to make Chromium the default
 // browser. Registers http and https.
 - (IBAction)makeDefaultBrowser:(id)sender {
   [self willChangeValueForKey:@"defaultBrowser"];
 
   ShellIntegration::SetAsDefaultBrowser();
   [self recordUserAction:L"Options_SetAsDefaultBrowser"];
   // If the user made Chrome the default browser, then he/she arguably wants
@@ skipping 321 matching lines @@
   [[NSNotificationCenter defaultCenter]
       postNotificationName:kUserDoneEditingPrefsNotification
                     object:self];
 }
 
 - (void)controlTextDidEndEditing:(NSNotification*)notification {
   [customPagesSource_ validateURLs];
 }
 
 @end