570858 - ChromeWorker doesn't exist from browser.xul/overlay js

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Ed Lee :Mardak]

We're trying to get a ChromeWorker object to access ctypes, but the object doesn't exist from the overlay or script loaded from the overlay.

If I create a dummy xul chrome page, both Worker and ChromeWorker are there.

Are these supposed to be accessible from the overlay and/or Error Console? We were going to use nsIWindowMediator to grab a browser window to extract the ChromeWorker object because it's not available from a Cu.import script.

Comment 1

[Philipp von Weitershausen [:philikon]]

ChromeWorker should definitely be available in all XUL contexts (right now it is only available if you load a XUL page in a browser window, like Mardak says). It would also be cool to have it available in JS modules.

Comment 2

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

How are you loading the script in question? At first it sounds like this is just a <script> element inside an overlay file, but then you are saying that you are using Components.utils.import.

Comment 3

[Philipp von Weitershausen [:philikon]]

ChromeWorker isn't available in the context of a <script> in an overlay file. Which means getting a hold of it from JS modules by doing something like Services.wm.getMostRecentWindow(null).ChromeWorker, it doesn't work either.

Comment 4

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Please lets focus on one issue at a time. If ChromeWorker isn't available in a XUL overlay that just contains a markup like:

<script>
worker = new ChromeWorker();
if (!worker) {
  alert("It didn't work");
}
</script>

then that seems like a good place to start.

jst, mrbkap, does scripts in overlays execute in a different context than the main xul document? It surprises me if that is the case.

Comment 5

[Philipp von Weitershausen [:philikon]]

I'm not sure it's main XUL document vs overlay. It seems to be more like window XUL vs XUL loaded within the browser.

Comment 6

[Johnny Stenback (:jst)]

Please explain what (In reply to comment #5)
> I'm not sure it's main XUL document vs overlay. It seems to be more like window
> XUL vs XUL loaded within the browser.

Please explain what you mean with "window XUL" vs "XUL loaded within the browser".

Comment 7

[Philipp von Weitershausen [:philikon]]

Basically our observation is that ChromeWorker is available in XUL documents that are loaded in a browser content window (e.g. about:config) whereas it's not in a Firefox overlay (which I consider "window XUL").

Comment 8

[Johnny Stenback (:jst)]

Can someone create a test extension or something that shows this problem?

Comment 9

[Philipp von Weitershausen [:philikon]]

Attachment: Test extension

Here's a test extension. When you start Firefox, it should dump() "ChromeWorker is [object ChromeWorker]" to stdout, but what actually happens is you get an exception in the error console:

  Error: ChromeWorker is not defined
  Source File: chrome://testchromeworker/content/ff-overlay.js
  Line: 1

Now, if you type chrome://testchromeworker/content/ff-overlay.xul into the browser location bar, the dump() message appears just fine.

Comment 10

[Johnny Stenback (:jst)]

Ben, can you have a look at this?

Comment 11

[Mike Connor [:mconnor]]

If this is still an issue, it should block, as this is the last big bit of CPU on the main thread for Sync.

Comment 12

[Johnny Stenback (:jst)]

Ben, can you dig into this a bit?

Comment 13

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

My impression was that we know what's going on here. Apparently we run overlays in some special type of context. Mrbkap might know more.

Comment 14

[Ben Turner (not reading bugmail, use the needinfo flag!)]

Attachment: Patch

This was backwards!

Comment 15

[Ben Turner (not reading bugmail, use the needinfo flag!)]

http://hg.mozilla.org/mozilla-central/rev/b9c3b2e1494a