PR# 12091 Clicking "X" to close Editor tab often has no effect

Clicking the "X" for an Editor tab to close that tab often has no effect
(tab not closed).  It looks like this is because any movement of the mouse
between the button press and the button release (even one pixel) causes the
action not to fire.  Perhaps this is because once the cursor position changes,
it is interpreted as a drag-and-drop rather than a button press/release.

In any case, this is very confusing and makes the interface seem buggy.
Maybe the mouse needs to first move
some minimum number of pixels away from its original position (2 or 3)
before the operation is converted into drag-and-drop.  Or perhaps a button
press when over the "X" needs to be treated differently, so that it doesn't
become a drag-and-drop operation.

This is all speculation.  But clicking on the "X" and not having the Editor tab
disappear is an unexpected and undesirable behavior from a user viewpoint.

At revision#67325, if end user first pressed left button and mouse keep moving in the editor close button area, the release the left button, the editor will be closed. If end user first pressed left button, then move the pointer outside the close button area, the editor close action will not be fired. This bug is fixed.

Thanks for your report.