[bug 1131736] Remove TinyMCE activation button.
[bug 1131736] Remove TinyMCE activation button.

This removes TinyMCE activation button but does not remove any other
code related to TinyMCE yet.

liu21st/masterfirefoxos,craigcook/masterfirefoxos,mozilla/masterfirefoxos,enng0227/masterfirefoxos,glogiotatidis/masterfirefoxos,enng0227/masterfirefoxos,enng0227/masterfirefoxos,liu21st/masterfirefoxos,glogiotatidis/masterfirefoxos,glogiotatidis/masterfirefoxos,mozilla/masterfirefoxos,liu21st/masterfirefoxos,glogiotatidis/masterfirefoxos,craigcook/masterfirefoxos,mozilla/masterfirefoxos,liu21st/masterfirefoxos,enng0227/masterfirefoxos,craigcook/masterfirefoxos,craigcook/masterfirefoxos,mozilla/masterfirefoxos