This method releases the device context (DC).
HRESULT ReleaseDC( OLE_HANDLE hDC );
NOERROR indicates success. If an error occurs, the appropriate HRESULT value is returned.
This method fails if the DC is not one that was retrieved by a call to IFMDraw::GetDC. Every call to IFMDraw::GetDC must be matched by a call to IFMDraw::ReleaseDC.