fix bug 56569 ("Create pages with form" and sfEditFormPreloadText)

The sfEditFormPreloadText hook was only called, when a preload was required (implicitly when saving an existing page or explicitly using the preload parameter).

It is now called in every case.

Change-Id: I66b9621b8df6d7e39823e14a20847452e3aab3f2
Merge "fix bug 56569 ("Create pages with form" and sfEditFormPreloadText)"