Fix vertical positioning of text field in the combo box editor associated with wxPG property under wxMSW.

Vertical position of text field in wxOwnerDrawnComboBox control (instantiated at property selection) doesn't need any special adjustment.

Closes #16556.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77687 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775