1060433 - nsIDOMWindowUtils.getScrollbarSize fails with e10s content

Status: RESOLVED INVALID

(Core :: DOM: Content Processes, defect, P3)

Description

[Jim Mathies [:jimm]]

http://mxr.mozilla.org/mozilla-central/ident?i=getScrollbarSize&tree=mozilla-central&filter=

STR:

1) open a new e10s window
2) open a single tab to google.com
3) open the browser console and eval:

let sbWidth = {}, sbHeight = {}; gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).getScrollbarSize(false, sbWidth, sbHeight);

result:

undefined
Permission denied to access property 'value'

Properties seem to work - 

gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).imageAnimationMode;
0
gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).docCharsetIsForced;
false

some methods work -

gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).getCursorType();
34

gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).elementFromPoint(10, 10, true, true);
<div class="gb_0 gb_Ic gb_f gb_Hc gb_Lc" style="min-width: 297px;">

I haven't tested everything, presumably we have tests that test all of this, some of which might be failing.

Comment 1

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Blake ran into this problem as well. It's a regression from bug 1052093. The code needs to look like this:

let sbWidth = {__exposedProps__: {'value': 'rw'}}, sbHeight = {...same...}; gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils).getScrollbarSize(false, sbWidth, sbHeight);

We probably need to figure out a way to fix this.

Comment 2

[Jim Mathies [:jimm]]

Presumably this affects anything with an out parameter, of which there are a few calls.

Comment 3

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Blake, what do you think about the idea of having some special-case code in the CPOW set handler? It would detect if the property name is "value", if the object's proto is Object.prototype, and if the "value" property doesn't already exist. In that case it would bypass the COW.

Comment 4

[Blake Kaplan (:mrbkap) (inactive)]

(In reply to PTO(back 9/9) Bill McCloskey (:billm) from comment #3)
> Blake, what do you think about the idea of having some special-case code in
> the CPOW set handler? It would detect if the property name is "value", if
> the object's proto is Object.prototype, and if the "value" property doesn't
> already exist. In that case it would bypass the COW.

Is this still necessary with the change to which junk scope we use in the parent? If so, then it sounds OK to me for now but we really need to find a better solution.

Comment 5

[Jens Stutte [:jstutte]]

Today the entire gBrowser.tabs[0].linkedBrowser.contentDocumentAsCPOW is undefined in the browser console. I assume this makes this bug invalid today, but feel free to re-open it or file a new one, of course.

Comment 6

[Andrew McCreight [:mccr8]]

Yes, CPOW support was removed a while ago.