Jesse Ruderman Reporter
	Description • 17 years ago

Loading the testcase triggers:

###!!! ASSERTION: no user stylesheets in styleset, but we have one!: 'numBefore > 0', file /Users/jruderman/trunk/mozilla/layout/base/nsPresShell.cpp, line 1824

This is a regression from within the last few days.

	Jesse Ruderman Reporter
	Comment 2 • 17 years ago

This assertion is triggered when loading http://online.wsj.com/public/us.

	Bob Clary [:bc] (inactive)
	Comment 3 • 17 years ago

reproducible in winxp/linux as well and #6 in a recent top site run with over 1300 occurrences.

	Jeff Walden [:Waldo]
	Comment 4 • 17 years ago

It's one of the more visible assertions in Mochitest runs in debug builds, too; I don't have access to a machine to determine which test(s) cause it.

	Boris Zbarsky [:bzbarsky] Assignee
	Comment 5 • 17 years ago

This is a regression from bug 310165.

The problem is that setting up the pref stylesheet fails if there is non-chrome script on the JS stack, because presshell uses the CSSOM API to set it up, and we added security checks to those calls (in particular to InsertRule).

We can either push null JSContexts on the stack in a bunch of places in presshell and in nsMathMLFrame, or we need to add a non-scriptable version of InsertRule that skips the security check.

David, do you have a preference?

Oh, and this bug can easily lead to pages without the pref stylesheet applied, so I think we need to block on it.

	David Baron :dbaron:
	Comment 6 • 17 years ago

I don't have a preference, other than whichever seems simpler and more maintainable.

	David Baron :dbaron:
	Comment 9 • 17 years ago

Comment on attachment 288927 [details] [diff] [review]
Same as diff -w

r+sr=dbaron.

Should the InsertRule security check be changed to fail if there's nothing on the context stack?

	Boris Zbarsky [:bzbarsky] Assignee
	Comment 10 • 17 years ago

You mean so that these things won't randomly work sometimes and randomly fail at other times?  That seems like a good idea.  I'll make that change before checking in.

	Boris Zbarsky [:bzbarsky] Assignee
	Comment 12 • 17 years ago

Checked in.

	Jesse Ruderman Reporter
	Comment 13 • 17 years ago

Crashtest checked in.