Only (and always) put URLs in NSLinkAttributeName.

chrome/browser/ui/cocoa/confirm_bubble_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.
 
 #import "chrome/browser/ui/cocoa/confirm_bubble_cocoa.h"
 
 #include "base/strings/string16.h"
 #include "chrome/browser/themes/theme_service.h"
 #import "chrome/browser/ui/cocoa/confirm_bubble_controller.h"
 #include "chrome/browser/ui/confirm_bubble.h"
@@ skipping 196 matching lines @@
   NSString* messageText = [controller_ messageText];
   NSMutableDictionary* attributes = [NSMutableDictionary dictionary];
   base::scoped_nsobject<NSMutableAttributedString> attributedMessage(
       [[NSMutableAttributedString alloc] initWithString:messageText
                                              attributes:attributes]);
   NSString* linkText = [controller_ linkText];
   if (linkText) {
     base::scoped_nsobject<NSAttributedString> whiteSpace(
         [[NSAttributedString alloc] initWithString:@" "]);
     [attributedMessage.get() appendAttributedString:whiteSpace.get()];
-    [attributes setObject:[NSString string]
+    [attributes setObject:[controller_ linkURL]
                    forKey:NSLinkAttributeName];
     base::scoped_nsobject<NSAttributedString> attributedLink(
         [[NSAttributedString alloc] initWithString:linkText
                                         attributes:attributes]);
     [attributedMessage.get() appendAttributedString:attributedLink.get()];
   }
   [[messageLabel_.get() textStorage] setAttributedString:attributedMessage];
   [messageLabel_.get() setHorizontallyResizable:NO];
   [messageLabel_.get() setVerticallyResizable:YES];
   [messageLabel_.get() setEditable:NO];
@@ skipping 47 matching lines @@
 
 - (void)clickCancel {
   [self cancel:self];
 }
 
 - (void)clickLink {
   [self textView:messageLabel_.get() clickedOnLink:nil atIndex:0];
 }
 
 @end