This is a speculative fix for a crash we are seeing in `menuDidClose`. We
can't repro the crash but the traces have it happening in this method
and just by reading through the impl the only part that jumps out as
Might Crash is this `model_` call. Other methods in the menu controller
check `model_` before using it so it probably makes sense to do that here
as well.
Fixes#18808
Previously, the triggeredByAccelerator flag would be entirely coupled with whether or not the modifier keys were being used or not.
This PR swaps out the ui::EventFlagsFromModifiers([event modifierFlags])) call in the macOS code to ui::EventFlagsFromNSEventWithModifiers(event, [event modifierFlags])). The latter outputs flags that take into account mouse click events on top of modifier flags (see Chromium documentation).
The business logic to detect triggeredByAccelerator is then changed to exclude any mouse click flags.
