Remove workaround for slow scrolling in wxStyledTextCtrl.

We don't need to drop mouse wheel events coming too fast after the previous
commit as now scrolling in wxStyledTextCtrl works quickly enough.

Closes #9057.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72255 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/stc/stc.h

@@ -4291,9 +4291,6 @@ protected:
 
     bool                m_lastKeyDownConsumed;
 
-    // Time until when we should ignore any new mouse wheel events.
-    wxLongLong m_timeToBlockWheelEventsUntil;
-
     friend class ScintillaWX;
     friend class Platform;
 #endif // !SWIG