Done automatically using the master version of MW codesniffer and
running composer fix.
Bug: T192167
Change-Id: If6b40f515fde32ab5eff074a90e821c30c791827
Factored out some minor parts about building editor CSS classes.
getEditConflictMainTextBox() mainly mirrors showTextbox1 parts not
included were moved to the EditPage.
Change-Id: I671e095acc08382dd0a1c3d167fdaaa623ec5499