TradioGroup and TCheckGroup: fix accessing Items inside Items.BeginUpdate/Items.EndUpdate.
Fixes issue #0024753.


git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42772 4005530d-fff6-0310-9dd1-cebe43e6787f
SynEdit: SynCompletion, refactor usage of OnUtf8Key (no longer internally used. Moved event to be called before any built in processing 

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42773 4005530d-fff6-0310-9dd1-cebe43e6787f
TradioGroup and TCheckGroup: fix error in r42772: reverse logic in calling UdateAll / UpdateInternalObjectList.


git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42774 4005530d-fff6-0310-9dd1-cebe43e6787f