571438 - MayHavePaintEventListener fails for non-e10s message manager

Status: RESOLVED FIXED

(Core :: IPC, defect)

Description

[Mark Finkle (:mfinkle) (use needinfo?)]

I am moving the DOM event handlers out of Fennec's chrome front-end and moving them to a content process frame script. I found that MayHavePaintEventListener returns FALSE, even though I have added a "MozAfterPaint" event listener in the frame script.

http://mxr.mozilla.org/mozilla-central/source/layout/base/nsPresContext.cpp#2058

Stepping through in GDB, nsCOMPtr<nsIInProcessContentFrameMessageManager> mm is NULL and none of the other checks trigger, so I get no "MozAfterPaint" event fired.

I then added a simple dummy event listener for "MozAfterPaint" back in the front-end chrome. Then I was able to get the "MozAfterPaint" event fired in the chrome script _and_ in the frame content script.

As I mentioned, this is happening in a mozilla-central, non-e10s message manager build.

Comment 1

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

I thought I had fixed this, but apparently I forgot to change the fix when
I moved to another event propagation route.

Comment 2

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

Attachment: patch

This depends on Bug 568975.

I have manual tests for this in my test-mm.xul.
I'll mochitestify those tests.

Comment 3

[Mark Finkle (:mfinkle) (use needinfo?)]

(In reply to comment #2)
> Created an attachment (id=450637) [details]
> patch
> 
> This depends on Bug 568975.
> 
> I have manual tests for this in my test-mm.xul.
> I'll mochitestify those tests.

Comment 4

[Mark Finkle (:mfinkle) (use needinfo?)]

I meant to say, this bug is breaking the Fennec nightly.

Comment 5

[Mark Finkle (:mfinkle) (use needinfo?)]

Comment on attachment 450637 [details] [diff] [review]
patch

Just an update: I applied this patch and built Fennec. Works great. MozAfterPaint is being fired.

Comment 6

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

http://hg.mozilla.org/mozilla-central/rev/758a20968e2e

Comment 7

[Mark Finkle (:mfinkle) (use needinfo?)]

This fix may have regressed MozAfterPaint firing from remote=true web content scripts

Comment 8

[Mark Finkle (:mfinkle) (use needinfo?)]

Testing on electrolysis branch, local pages work fine (MozAfterPaint is fired) but remote pages do not fire the event in the content script

Comment 9

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

This fix was for m-c, not for e10s. Seems like the m-c -> e10s merge removed
some code from e10s.