312232 - getScreenCTM fails somehow in xulrunner builds

Status: RESOLVED FIXED

(Core :: SVG, defect)

Description

[Rob Adams]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1) Gecko/20051012 Firefox/1.6a1
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1) Gecko/20051012 Firefox/1.6a1

Under XULRunner, for some reason calling getScreenCTM fails: 
[JavaScript Error: "uncaught exception: [Exception... "Component returned
failure code: 0xbfaaeeac [nsIDOMSVGLocatable.getScreenCTM]"  nsresult:
"0xbfaaeeac (<unknown>)"  location: "JS frame ::
https://bugzilla.mozilla.org/attachment.cgi?id=197708 :: doDrag :: line 11" 
data: no]"]

Load https://bugzilla.mozilla.org/attachment.cgi?id=197708 in an iframe for
example in any xulrunner application.

I'll also attach a very minimal xulapp testcase that also shows the problem. 
Click on the black square in the test case.

Reproducible: Always

Comment 1

[Rob Adams]

Attachment: Simple test case. Click on the black square. Should show coordinates.

Comment 2

[Benjamin Smedberg]

Is this perhaps a problem with any document loaded in a toplevel window (not in
a <xul:browser>, <iframe>, whatever)? What happens when you load the equivalent
SVG using firefox -chrome "http://whateverurl.svg"?

Comment 3

[Rob Adams]

I apologize; this appears to only happen in my personal build.  I'll mess around
with it more.

Comment 4

[Rob Adams]

Ok this is caused by an unitialized return value in GetViewboxToViewportTransform.

Trivial patch to be attached.

Comment 5

[Rob Adams]

Attachment: initialize the return value in GetViewboxToViewportTransform

Comment 6

[Jonathan Watt [:jwatt]]

Comment on attachment 199436 [details] [diff] [review]
initialize the return value in GetViewboxToViewportTransform 

Please just initialize at the declaration point. And please fix up the same
method on nsSVGMarkerElement while you're there.

Comment 7

[Rob Adams]

Attachment: Style change and also update nsSVGMarkerElement::GetViewboxToViewportTransform as well

Comment 8

[Jonathan Watt [:jwatt]]

Comment on attachment 199467 [details] [diff] [review]
Style change and also update nsSVGMarkerElement::GetViewboxToViewportTransform as well

r=me and requesting sr from tor.

Comment 9

[Benjamin Smedberg]

Comment on attachment 199467 [details] [diff] [review]
Style change and also update nsSVGMarkerElement::GetViewboxToViewportTransform as well

jwatt/tor, can one of you land this on trunk for readams?

Comment 10

[Jonathan Watt [:jwatt]]

Done.

The patch is an obviously correct three line patch (exclucing the indentation
changes) to prevent us from returning an uninitialized nsresult. Up until
relatively recently we returned the correct value without any problems, so the
risk from this patch is very small. The value SVG authors, especially in chrome,
is significant I would think.

Comment 11

[Jonathan Watt [:jwatt]]

checked in on branch