Use escapejs filter on JavaScript strings

The escapejs filter will correctly escape single quotes from JavaScript
strings which may otherwise trigger syntax errors. In this case, the
issue was visible using the French translation.

Also removed a trailing paranthesis coming out of nowhere.

Change-Id: I25001815e17be5afa8eb28cc28c5423e3dcd973c
Closes-Bug: #1311047
Merge "Use escapejs filter on JavaScript strings"