Stop Scintilla timer when the control doesn't have focus.

This avoids excessive CPU load due to generating completely unnecessary timer
notifications for every wxSTC control in a program.

Closes #14938.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76665 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Fix spurious assert when creating multiline wxTextCtrl from XRC.

Don't try to set the hint unconditionally, this doesn't work with multiline
text controls and so resulted in an assert when trying to create one from XRC
since the changes of r76629.

Closes #16317.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76666 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775