According to the doc comment of Title::invalidateCache(), its function is to update page_touched. This is a fine thing for a function to do. Lately, two more things have been added to it:
- Clear action=info cache
On the face of it, it would seem that WikiPage::onArticleEdit() would be a more appropriate place for these two activities, and indeed, one of them (the HTMLFileCache update) is already there.
One problem with adding the action=info update to Title::invalidateCache() is that the data on action=info needs to be updated when the page is edited, and Title::invalidateCache() is not called when the page is edited.
Another problem is that Title::invalidateCache() is called in circumstances when the data on action=info is *not* invalidated, for example when a revision is deleted with Special:RevisionDelete.
So I suggest removing the action=info cache clear from Title::invalidateCache(), adding it to WikiPage::onArticleEdit() and WikiPage::onArticleCreate() (factored out of course), and also adding it to any other Title::invalidateCache() caller that appears to need it.
Assigning to Tyler since he added the action=info cache clear.