DevTools: Linkify console stacks with blackboxing consideration.

Source/devtools/front_end/inspectorSyntaxHighlight.css

 /*
  * Copyright (C) 2009 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 97 matching lines @@
 .webkit-html-external-link {
     /* Keep this in sync with view-source.css (.webkit-html-external-link) */
     text-decoration: none;
 }
 
 .webkit-html-external-link:hover {
     /* Keep this in sync with view-source.css (.webkit-html-external-link:hover) */
     text-decoration: underline;
 }
 
+.webkit-html-blackbox-link {
+    opacity: 0.6;
+}
+
 .webkit-html-end-of-file {
     /* Keep this in sync with view-source.css (.webkit-html-end-of-file) */
     color: rgb(255, 0, 0);
     font-weight: bold;
 }