Add comments for grep & Fix double-whitespaces

* Give grep a chance to find the usages
* Fix double-whitespaces, spotted by 아라
http://translatewiki.net/wiki/Thread:Support/About_MediaWiki:Revreview-newest-quality/en

Change-Id: I7e8c6e163fdcdf7d025e76e9df20d8699298e1ae