Fix incorrect rendering of checked menu items on Windows Classic

Fix incorrect rendering of checked menu items on Windows Classic

Modify rendering of checked menu items when using Windows Classic
style to be more native looking.

Changes:
* Checked menu items with no icon are not drawn sunken
* Disabled checked menu items with an icon have a plain background
  instead of a checkerboard pattern same as when enabled
* Check mark is drawn with highlighted text color when selected to
  match text
* Fix check mark offset for disabled unselected checked menu item
  as the entire check mark was drawn shifted (1, 1)
* Fix color of check mark shadow for disabled unselected checked
  menu item as it was same color as the check mark when it should
  be a light color

Task-number: QTBUG-15098
Merge-request: 2513
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@nokia.com>
(cherry picked from commit e89a2b72050dd782da16ff24bc2eb84dc36ed6a5)