Use `rawHtml` in `testWymManipulation`.
Merge branch 'testWymManipulationRawHtml' into

noPrepareDocInRawHtml
Fix the empty document test.
Merge branch 'testWymManipulationRawHtml' into

firefoxKeepDesignModeOn
Merge branch 'noPrepareDocInRawHtml' into

firefoxKeepDesignModeOn