DERBY-6662; DatabaseMetaData.usesLocalFiles() returns true for in-memory databases
   backport of revision 1627895 and revision 1628009 from the 10.11 branch;
   making the affected methods return false for in-memory databases and adding a test.


git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/branches/10.10@1628025 13f79535-47bb-0310-9956-ffa450edef68