patch 9.1.1084: Unable to persistently ignore events in a window and its buffers

Problem:  Unable to persistently ignore events in a window and its buffers.
Solution: Add 'eventignorewin' option to ignore events in a window and buffer
          (Luuk van Baal)

Add the window-local 'eventignorewin' option that is analogous to
'eventignore', but applies to a certain window and its buffers. Identify
events that should be allowed in 'eventignorewin', adapt "auto_event"
and "event_tab" to encode this information. Window context is not passed
onto apply_autocmds_group(), and when to ignore an event is a bit
ambiguous when "buf" is not "curbuf", rather than a large refactor, only
ignore an event when all windows into "buf" are ignoring the event.

closes: #16530

Signed-off-by: Luuk van Baal <luukvbaal@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/option.h b/src/option.h
index df5bf4d..70206f3 100644
--- a/src/option.h
+++ b/src/option.h
@@ -1288,6 +1288,7 @@
 #ifdef FEAT_DIFF
     , WV_DIFF
 #endif
+    , WV_EIW
 #ifdef FEAT_FOLDING
     , WV_FDC
     , WV_FEN