Fix a crash in the print service settigns.

 When the search view is attached and detached we announce that
 for accessibility. The trouble is that if the activity is being
 torn down we are trying to access resources from a fragment that
 is detached and the qcrash occurs. This change does not try to
 access resources if the activity is finishing and also we do not
 load resource strings if accessibility is not enabled.

bug:11127814

Change-Id: If3e97b6e94687775386a43c8fa54fd45140306eb