Impact of merging feature/chained-text-boxes to master

Hi all,

this is to describe some changes (in code and behavior) that should occur
merging branch  "feature/chained-text-boxes" to master.
The branch implements (a prototype of) text box chaining: the possibility
of having  logically linked text boxes in Draw (and potentially Impress) so
that text content beyond what box size allows goes automatically to the
next link. (And, the other way around, when space becomes available in
previous links this also gets filled with text from "next" boxes).

What was done (Main Blocks of Code Change)
---------------------------------------------------------------
1a) Detection of overflow/underflow of text (editeng);
1b) Changes in how box sizes are computed for chainable boxes (SdrTextObj
in svx/svdraw. Specifically this commit
<http://cgit.freedesktop.org/libreoffice/core/commit/?h=feature/chained-text-boxes&id=21bd174f53de2bd4b4223919da2e901a8bdc52b4>
);
2) Transfer of text after overflow/underflow (mostly editeng, with
view-related aspects such as cursor motion in svx/svdraw);
3) Activation of triggers for overflow detection and text transfer (mostly
SdrObjEditView and OutlinerView, resp. svx/svdraw and editeng. One line was
changed in sd);
4) Definition of UNO properties and their loading code from files (by
attribute: "draw:chain-next-name" that defines Chainable boxes).

What may/will be affected
-----------------------------------
NOTE: The vast majority of the code above should only affect  LO behavior
for docs that have the tag in (4) set to something sensible.

Some things may be broken only for chainable boxes (I wonder about the
effects of (1b) for instance).

However, there are some changes that modify behavior for both Chainable and
non-Chainable boxes, in particular, bullet (3) above.
For this, I would look in particular at the commits in the attached file.

Cheers,
Matteo

commit 54b576c3b3bf3d67c5ffd4ae391f6c03e3647dc1
Author: matteocam <matteo.campanelli@gmail.com>
Date:   Mon Sep 7 20:01:35 2015 +0200

    Handle chaining for cutting and pasting
    
    Change-Id: Iec08e339a7f06c5fa56e67b42206b31c766f845b

commit 731000696b282f457a7e003297d4f158849825d4
Author: matteocam <matteo.campanelli@gmail.com>
Date:   Mon Sep 7 19:58:16 2015 +0200

    Handle DEL key for chaining
    
    Change-Id: I124b1adf6df3c42a58d45eaeb0e1e053c0eea4c9

commit 1a86da45320faf5f644c1a82c07bd9b522a2a351
Author: matteocam <matteo.campanelli@gmail.com>
Date:   Mon Sep 7 16:37:56 2015 +0200

    Enable chaining after a key is pressed
    
    Change-Id: I64351619dd0886f3bb0c080557864c46a17d737d

commit 3748019d58154b2851999c3ea9f2ab223c8e3bc3
Author: matteocam <matteo.campanelli@gmail.com>
Date:   Mon Sep 7 12:44:37 2015 +0200

    Change EndTextEdit behavior to support recursive overflow
    
    Change-Id: I14009fa2e91b19a850e45484de7cd234e872689a