[rAC, OSX] Use bubble windows for error messages.

chrome/browser/ui/cocoa/autofill/autofill_error_bubble_controller.h

+// Copyright (c) 2013 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.
+
+#ifndef CHROME_BROWSER_UI_COCOA_AUTOFILL_AUTOFILL_ERROR_BUBBLE_CONTROLLER_H_
+#define CHROME_BROWSER_UI_COCOA_AUTOFILL_AUTOFILL_ERROR_BUBBLE_CONTROLLER_H_
+
+#import <Cocoa/Cocoa.h>
+
+#include "base/mac/scoped_nsobject.h"
+#import "chrome/browser/ui/cocoa/base_bubble_controller.h"
+
+// Bubble controller for field validation error bubbles.
+@interface AutofillErrorBubbleController : BaseBubbleController {
+   base::scoped_nsobject<NSTextField> label_;
+}
+
+// Creates an error bubble with the given |message|. You need to call
+// -showWindow: to make the bubble visible. It will autorelease itself when the
+// user dismisses the bubble.
+- (id)initWithParentWindow:(NSWindow*)parentWindow
+                   message:(NSString*)message;
+
+@end
+
+
+#endif  // CHROME_BROWSER_UI_COCOA_AUTOFILL_AUTOFILL_ERROR_BUBBLE_CONTROLLER_H_