[Mac] Fix Cmd-W closing whole window under fullscreen.

chrome/browser/ui/cocoa/browser_window_controller.mm

 // Copyright (c) 2012 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/ui/cocoa/browser_window_controller.h"
 
 #include <cmath>
 #include <numeric>
 
 #include "base/command_line.h"
@@ skipping 957 matching lines @@
 
 - (BOOL)supportsFullscreen {
   // TODO(avi, thakis): GTMWindowSheetController has no api to move
   // tabsheets between windows. Until then, we have to prevent having to
   // move a tabsheet between windows, e.g. no fullscreen toggling
   NSArray* a = [[tabStripController_ sheetController] viewsWithAttachedSheets];
   return [a count] == 0;
 }
 
 // Called to validate menu and toolbar items when this window is key. All the
-// items we care about have been set with the |-commandDispatch:| or
-// |-commandDispatchUsingKeyModifiers:| actions and a target of FirstResponder
+// items we care about have been set with the -performClose:, -commandDispatch:
+// or -commandDispatchUsingKeyModifiers: actions and a target of FirstResponder
 // in IB. If it's not one of those, let it continue up the responder chain to be
 // handled elsewhere. We pull out the tag as the cross-platform constant to
 // differentiate and dispatch the various commands.
 // NOTE: we might have to handle state for app-wide menu items,
 // although we could cheat and directly ask the app controller if our
 // command_updater doesn't support the command. This may or may not be an issue,
 // too early to tell.
 - (BOOL)validateUserInterfaceItem:(id<NSValidatedUserInterfaceItem>)item {
   SEL action = [item action];
   BOOL enable = NO;
-  if (action == @selector(commandDispatch:) ||
+  if (action == @selector(performClose:) ||
+      action == @selector(commandDispatch:) ||
       action == @selector(commandDispatchUsingKeyModifiers:)) {
     NSInteger tag = [item tag];
     if (browser_->command_updater()->SupportsCommand(tag)) {
       // Generate return value (enabled state)
       enable = browser_->command_updater()->IsCommandEnabled(tag);
       switch (tag) {
         case IDC_CLOSE_TAB:
           // Disable "close tab" if the receiving window is not tabbed.
           // We simply check whether the item has a keyboard shortcut set here;
           // app_controller_mac.mm actually determines whether the item should
@@ skipping 1171 matching lines @@
 
 - (BOOL)supportsBookmarkBar {
   return [self supportsWindowFeature:Browser::FEATURE_BOOKMARKBAR];
 }
 
 - (BOOL)isTabbedWindow {
   return browser_->is_type_tabbed();
 }
 
 @end  // @implementation BrowserWindowController(WindowType)