[win32k]

- Revert the hack done in 47059 to apply a better solution.
- co_IntCreateWindowEx: Add the WNDS2_WMCREATEMSGPROCESSED flag to state2 member of WND after sending the WM_CREATE message.
- By setting this flag it can be examined elsewhere to determine if the window was created successfully.
- co_UserDestroyWindow: Examine above mentioned flag to make sure the windows was created before calling hook procedure to inform of destroying window.

svn path=/trunk/; revision=47073