QmlProfiler: Make sure that very narrow events can be hovered over

By giving the area the mouse "covers" a non-zero width events that last
only a very short time can be selected even if no pixel in the timeline
falls "into" them.

Task-number: QTCREATORBUG-11692
Change-Id: I53b74e2a770719872e0afc57740f7762636dc641
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
QmlProfiler: Remove pointless second check for endTime

If the selected events aren't in the specified time range the selection
should be fixed.

Change-Id: I8cb6b57054888433b5ebf66fce3b479b3266f86e
Reviewed-by: Kai Koehne <kai.koehne@digia.com>