Summary
-------

Remove pre-JDK 1.2 SecurityManager text and and related code from java.awt.Toolkit class

Problem
-------

Support for pre-JDK 1.2 SecurityManager was removed under JDK-8189750. So it is necessary to update classes in java.desktop module accordingly.

Solution
--------

It is necessary to update description of java.awt.Toolkit.getImage(URL u) and java.awt.Toolkit.createImage(URL u) to get rid of ���pre JDK 1.2 SecurityManager��� text. Also the corresponding fallback code should be removed from SunToolkit.checkPermission(URL u) and from the constructor of URLImageSource.

Specification
-------------

Changing API spec of java.awt.Toolkit.getImage(URL url)

from:

     * then {@code URLPermission} is used for security checks.
     * For compatibility with pre-1.2 security managers, if the access
     * is denied with {@code FilePermission} or {@code SocketPermission},
     * the method throws the {@code SecurityException}
     * if the corresponding 1.1-style SecurityManager.checkXXX method
     * also denies permission.
     * @param     url   the URL to use in fetching the pixel data.

to:

     * then {@code URLPermission} is used for security checks.
     * @param     url   the URL to use in fetching the pixel data.

Changing API spec of java.awt.Toolkit.createImage(URL url)

from:

     * then {@code URLPermission} is used for security checks.
     * For compatibility with pre-1.2 security managers, if the access
     * is denied with {@code FilePermission} or {@code SocketPermission},
     * the method throws the {@code SecurityException}
     * if the corresponding 1.1-style SecurityManager.checkXXX method
     * also denies permission.
     * @param     url   the URL to use in fetching the pixel data.

to:

     * then {@code URLPermission} is used for security checks.
     * @param     url   the URL to use in fetching the pixel data.