Force recalc of the keyloop for alerts.

chrome/browser/ui/cocoa/javascript_app_modal_dialog_cocoa.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.
 
 #include "chrome/browser/ui/cocoa/javascript_app_modal_dialog_cocoa.h"
 
 #import <Cocoa/Cocoa.h>
 #include <stddef.h>
 
 #include "base/i18n/rtl.h"
@@ skipping 122 matching lines @@
       NOTREACHED();
     }
   }
 }
 
 - (void)showAlert {
   DCHECK(nativeDialog_);
   DCHECK(!alertShown_);
   alertShown_ = YES;
   NSAlert* alert = [self alert];
+
+  [alert layout];
+  [[alert window] recalculateKeyViewLoop];
+
   [alert beginSheetModalForWindow:nil  // nil here makes it app-modal
                     modalDelegate:self
                    didEndSelector:@selector(alertDidEnd:returnCode:contextInfo:)
                       contextInfo:NULL];
 }
 
 - (void)acceptAlert {
   DCHECK(nativeDialog_);
   if (!alertShown_) {
     [self sendAcceptToNativeDialog];
@@ skipping 315 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(ChromeJavaScriptNativeDialogCocoaFactory);
 };
 
 }  // namespace
 
 void InstallChromeJavaScriptNativeDialogFactory() {
   app_modal::JavaScriptDialogManager::GetInstance()->SetNativeDialogFactory(
       base::WrapUnique(new ChromeJavaScriptNativeDialogCocoaFactory));
 }