[475829] Redirect xxxExecs calls to default display if no workbench

Redirect all the PlatformUI.getWorkbench().getDisplay().syncExec /
asyncExec / readAndDispatch calls to a specific method which will check
if the workbench is here and will use Display.getDefault() when the
workbench is not present.

Bug: 475829
Change-Id: Ib543ede26578db7354a28ac0ed59f54b7925e44c
Signed-off-by: Cedric Brun <cedric.brun@obeo.fr>
38 files changed