Review request for 6891707: Eliminate the java.io.FilePermission dependency on PolicyFile

[Mandy Chung]

Alan, Sean,

Can you review the fix for:
   6891707: Eliminate the java.io.FilePermission dependency on PolicyFile

Webrev:
   http://cr.openjdk.java.net/~mchung/6891707/webrev.00/

FilePermission and PolicyFile are the two callers to the 
sun.security.provider.PolicyFile.canonPath method. Adding a new class 
for the canonPath method seems unnecessary.  So the fix just duplicates 
the code in FilePermission class.

Thanks
Mandy