File.setWritable() / File.canWrite() not behaving as expected

SYNOPSIS
--------
File.setWritable() / File.canWrite() not behaving as expected

OPERATING SYSTEM
----------------
Windows

FULL JDK VERSION
----------------
Java 6, from 1.6.0_23 onwards
Not reproducible on Java 7

PROBLEM DESCRIPTION from LICENSEE
---------------------------------
If setWritable(false) returns true, canWrite() should return false.

From 1.6.0_23, canWrite() is returning true under these circumstances, which is not correct. The problem seems to be caused by an incomplete backport of the changes for CR 6728842 from Java 7 (see suggested fix).

TESTCASE
--------
import java.io.File;

public class Test {
    public static void main(String[] args){
        File f = new File("wibblefish");
        f.deleteOnExit();
        if (f.mkdirs())
            if (f.setWritable(false,false)) {
                if (f.canWrite()) {
                    System.out.println("Test failed");
                } else {
                    System.out.println("Test passed (setWritable() succeeded)");
                }
            } else {
                System.out.println("Test Passed (setWritable() failed)");
            }
    }
}

REPRODUCTION INSTRUCTIONS
-------------------------
Compile and execute the above given testcase.

Expected output:
Test passed (setWritable() succeeded)
OR
Test Passed (setWritable() failed)

Observed output:
Test failed

SUGGESTED FIX from LICENSEE
---------------------------
See Suggested Fix section of CR.