[platform-ui-dev] Startup Changes

[Kimberly Horne <kim@xxxxxxxxxxxxx>]

Code has been introduced that moves the startup procedure off of the  
UI thread which allowing us to paint the splash screen at regular  
intervals  Areas of startup that still require UI access as well as  
all calls out to user code are being synchronized on the UI thread  
such that to all third parties our startup routine SHOULD look the  
same with one small exception.  While we were able to prevent non- 
workbench runnables from running via calls to Display.syncExec and  
asyncExec during startup we haven't investigated preventing events  
being fired to display filters.  Because display filters are a fringe  
concern (and explicitly called out as being dangerous) we've left  
them alone for the time being.  If anyone has an issue with this  
please log a bug against platform-ui.

For information on this change please see https://bugs.eclipse.org/ 
bugs/show_bug.cgi?id=168617.