[PATCH] user32: Update exstyle when setting style in SetWindowLong.

[Piotr Caban]

Rockstar Games Launcher checks extended window style and exits if it is 
incorrect.

Signed-off-by: Piotr Caban <piotr(a)codeweavers.com>
---
  dlls/user32/tests/win.c | 18 +++++++++++++++++-
  dlls/user32/win.c       | 15 ++++++++++++---
  2 files changed, 29 insertions(+), 4 deletions(-)