[438603] Have tree refresh to create DTreeItem with all needed EObjects

Have tree refresh to create DTreeItem with all needed EObjects,
TreeItemStyle, RGBValues with default red/green/blue value to decrease
the number of EMF notifications in postcommit.

Bug: 438603
Change-Id: I506b5fde6f331967c6f6dbccce567336510dc859
Signed-off-by: Esteban Dugueperoux <esteban.dugueperoux@obeo.fr>
[444569] Fix issue with hidden edges because of scroll bar.

* Some edges can be masked because of a scrollbar on a container. If one
of the edge end is masked by the scroll size, the edge is masked too.
The OrthogonalLayout doesn't relocate the masked edges and that causes
wrong diagram bounds computation and persistent scroll bar if the old
edge location is out of the current bounds.

Bug: 444569
Change-Id: If9e00cdc273f05cd897c6fb22d6080f53aececd0
Signed-off-by: Florian Barbin <florian.barbin@obeo.fr>
[444569] Add the ResetOrigin SwtBot test

Bug: 444569
Change-Id: I8d62d496b38055b60b3727910eb5257578abfb43
Signed-off-by: Florian Barbin <florian.barbin@obeo.fr>
[444569] Move the reset origin action after the arrange menu.

Bug: 444569
Change-Id: I7104a13633e763ea610a4367780da9375d3fed00
Signed-off-by: Florian Barbin <florian.barbin@obeo.fr>
[443108] Move "remove Bend-points" action after the format menu

Bug: 443108
Change-Id: Idbf1716dfdd033689ea9d88e153a78ba2311a18c
Signed-off-by: Florian Barbin <florian.barbin@obeo.fr>
[441483] Only execute testGMFUnset in the right context

The test depends on a currently unmerged patch for GMF Notation (see
bug 412078); avoid executing it (and failing) if we run with an official,
non-patched version of GMF Notation.

Bug: 4414837
Change-Id: I21bdc438aa50b2b5967ec9f01c1b50dc468eeba3
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>
[tests] Adjust the editor's title lookup for Luna

Since 09bbfb0, most tests use a different API to open the editors and
thus do not benefit from the workaround which was placed in
UIDiagramRepresentation.getEditor(). Put the workaround also in the main
openRepresentation() method which is now used.

Change-Id: I0cc3e7041653789e5c89b049f7a0a6ae2ee5f503
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>