DERBY-6504; change AllocPage.ReadContainerInfo to catch ArrayIndexOutOfBoundsException and turn it into Derby error.
   Adjusting lang/ErrorCodeTest to reflect the new message.


git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1600721 13f79535-47bb-0310-9956-ffa450edef68