E.g. Ctrl+Left/Right, Ctrl+Shift+Del/Backspace, double-click to select
word...

These are all implemented in SwCursor, so they need a layout passed to
them from the SwViewShell.

There was a bug in the while loop in SwCursor::GoSentence() case
NEXT_SENT that triggered assert in the mapping code when the
endOfSentence() returned the length of the SwTextNode but then it was
incremented once more.

Change-Id: Ic3866860a8c07774dce35952271c207eb6e7d182