[Mac] Enable "Edit Search Engines" in Omnibox context menu.

chrome/browser/cocoa/preferences_window_controller.mm

Index: chrome/browser/cocoa/preferences_window_controller.mm
diff --git a/chrome/browser/cocoa/preferences_window_controller.mm b/chrome/browser/cocoa/preferences_window_controller.mm
index df214f395aac1d5ec588cea8d564f3a74cdcc8ef..526cc68ffdb9acefba0d99c742323b57828a7d4c 100644
--- a/chrome/browser/cocoa/preferences_window_controller.mm
+++ b/chrome/browser/cocoa/preferences_window_controller.mm
@@ -580,24 +580,8 @@ enum { kHomepageNewTabPage, kHomepageURL };
   [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 {
-  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];
+  [KeywordEditorCocoaController showKeywordEditor:profile_];
 }
 
 // Called when the user clicks the button to make Chromium the default