Bug 2236: Fixed bugs in PathMap.

  * equals(Object): mapIndex field values need to be compared using
    Objects.equals().
  * hashCode(): Fixed NPE if mapIndex is null.

Change-Id: Iadd25f620dba1af7fb08c262f22a97ee978e08a3
Signed-off-by: Shigeru Yasuda <s-yasuda@da.jp.nec.com>
Merge "Bug 2236: Fixed bugs in PathMap."