Better handling of broken applet codebase

Source/core/html/HTMLAppletElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
  * Copyright (C) 2004, 2005, 2006, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 133 matching lines @@
     const AtomicString& code = getAttribute(codeAttr);
     paramNames.append("code");
     paramValues.append(code.string());
 
     // If the 'codebase' attribute is set, it serves as a relative root for the file that the Java
     // plugin will load. If the 'code' attribute is set, and the 'archive' is not set, then we need
     // to check the url generated by resolving 'code' against 'codebase'. If the 'archive'
     // attribute is set, then 'code' points to a class inside the archive, so we need to check the
     // url generated by resolving 'archive' against 'codebase'.
     KURL urlToCheck;
-    KURL rootURL = codeBase.isNull() ? document().url() : document().completeURL(codeBase);
+    KURL rootURL;
+    if (!codeBase.isNull())
+        rootURL = document().completeURL(codeBase);
+    if (rootURL.isNull() || !rootURL.isValid())
+        rootURL = document().url();
+
     if (!archive.isNull())
         urlToCheck = KURL(rootURL, archive);
     else if (!code.isNull())
         urlToCheck = KURL(rootURL, code);
     if (!canEmbedURL(urlToCheck))
         return;
 
     const AtomicString& name = document().isHTMLDocument() ? getNameAttribute() : getIdAttribute();
     if (!name.isNull()) {
         paramNames.append("name");
@@ skipping 63 matching lines @@
 
     if (!document().contentSecurityPolicy()->allowObjectFromSource(url)
         || !document().contentSecurityPolicy()->allowPluginTypeForDocument(document(), m_serviceType, m_serviceType, url)) {
         layoutEmbeddedObject()->setPluginUnavailabilityReason(LayoutEmbeddedObject::PluginBlockedByContentSecurityPolicy);
         return false;
     }
     return true;
 }
 
 }