Windows: QtQuick Controls styling, redraw, and keyboard handling problems.

All the problems listed here are seen in the "<path-to-Qt5.3.0>\Examples\Qt-5.3\quick\controls\gallery" example application.

1) MenuBar styling is incorrect in Windows classic theme. When a menu is open, the top-level title of the open menu has wrong (absent) styling.
See screenshot: menubar.png

2) Incorrect styling after theme switching. With the gallery example running, after switching themes from Windows 7 default theme to classic theme and vice versa, parts of the window are not styled correctly.
See screenshots: theme-switching-classic-to-default.png, theme-switching-default-to-classic.png

3) TabView tabs look a tiny bit squashed when using classic theme.
See screenshot: tabview.png

4) ComboBox item cut off. The last item in a ComboBox is slightly cut off at the bottom. Can be seen in both default and classic themes, more obvious in classic theme.
See screenshot: combobox-item-cut-off.png

5) ComboBox redraw problem when using classic theme. When the long ComboBox containing all the font names is opened it extends beyond the window bounds. When it is then closed some parts of the window are not redrawn, with bits of the window frame where the ComboBox overlapped still displaying the ComboBox contents. This also affects the Windows taskbar and other windows if the ComboBox happens to be drawn over them.
See screenshot: combobox-redraw.png

6) MenuBar key handling is wrong. Launch the native Windows Calculator application and observe the behaviour after pressing and releasing Alt to focus the menu bar and then using the arrow keys on the keyboard and the shortcut keys to navigate the menus. Then try doing the same in the gallery example. It is buggy.

After pressing Alt to focus the menu, pressing it a second time does not unfocus the MenuBar. If the "lorem ipsum" TextArea on the first tab of the gallery example happens to have focus when Alt is pressed and released the first time, pressing the down arrow to open the menu continues to move the cursor in the TextArea, and the menu only opens once the cursor has reached the last row of text. If instead Alt is pressed and released and then the menu shortcut key is pressed, rather than opening the menu the character is inserted into the TextArea as though still inputting text there. Only if Alt and the shortcut key are pressed at the same time does the menu open. This is incorrect behaviour.

Also when a menu is open, pressing the shortcut key of a different top-level menu then opens that different menu. This is incorrect behaviour as an item in the previously open menu may use the same shortcut key and should take priority. Even if there is no such menu item this is still incorrect behaviour and the key stroke should have no effect until Escape is pressed to close the open menu and give focus back to the top-level menu items.

MenuBar key handling should match the native behaviour as seen in the Calculator application.