343613 - Make EventStateManager to use nsWeakFrame

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Olli Pettay [:smaug][[e-mail]]]

EventStateManager should use nsFrameDestroyNotifier to check whether some 
nsFrame objects are alive. This simplifies the code a bit - no need to have two
ways to do the same thing.

Comment 1

[Olli Pettay [:smaug][[e-mail]]]

Attachment: proposed patch

This makes it quite difficult to use dead nsIFrames in ESM. No need to call
SetFrameExternalReference everywhere.

Comment 2

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Comment on attachment 229081 [details] [diff] [review]
proposed patch

This is good. However, keep in mind that wherever we're using nsWeakFrame, we're creating potential problems if content gets restyled; we end up just aborting when in many cases we should be able to carry on. In many cases the *real* (not necessarily branch-compatible) fix is to move logic to operate on content instead of frames.

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

(In reply to comment #2)
>... we end up just
> aborting when in many cases we should be able to carry on. In many cases the
> *real* (not necessarily branch-compatible) fix is to move logic to operate on
> content instead of frames.

I understand that, but until the logic has moved, nsWeakFrame is needed.