56226 - text/html treeitem in Helper App panel is broken (NS_NOINTERFACE)

Status: VERIFIED FIXED

(SeaMonkey :: UI Design, defect, P3)

Description

[John Morrison]

Do Edit->Preferences, then select the Navigator->Helper Applications
panel (pref-applications.xul).

Then mousedown on the 'text/html' entry in the tree -- this JS error
is thrown:

JavaScript error:
 line 4: uncaught exception: [Exception... "Component returned failure code:
0x80004002 (NS_NOINTERFACE) [nsISupports.QueryInterface]"
nsresult: "0x80004002 (NS_NOINTERFACE)"
location: "JS frame :: chrome://communicator/content/pref/overrideHandler.js
:: anonymous :: line 103"  data: no]

The same error also occurs when you press the 'Edit...' button while this
treeitem is selected, and the Edit panel comes up blank.

chrome://communicator/content/pref/overrideHandler.js

 98 if (extensionTargets) {
 99 extensionTargets =
extensionTargets.QueryInterface(Components.interfaces.nsISimpleEnumerator);
100 while (extensionTargets.hasMoreElements()) {
101 var currentExtension = extensionTargets.getNext();
102 if (currentExtension) {
103 currentExtension =
currentExtension.QueryInterface(Components.interfaces.nsIRDFLiteral);
104 extString += currentExtension.Value.toUpperCase() + " ";
105 }

Again, Ben says "not good". Details?

Comment 1

[don]

Minus.  I don't think most users will try to edit it.

Comment 2

[Blake Ross]

Given that flaky and broken helper app controls were one of the most prominent  
complaints of 6.0, beta1 really shouldn't ship without this.

Comment 3

[Paul Chen]

nav triage team:

Actually, this thing shouldn't be editable, reassigning to pchen, setting
mozilla0.8 target milestone

Comment 4

[selmer (gone)]

We're past time to cut these low priority bugs from mozilla0.8.  Please update
these bugs today. 

Comment 5

[Paul Chen]

Ok, so the problem is that the prepopulated mimeTypes.rdf in
mozilla/profile/defaults/ doesn't jive with what the helper apps prefs code is
looking for. Fix is to remove about attributes from NC:fileExtensions tags. This
prevents the exception in overrideHandler.js:103, and this is the form it spits
out back to . Since the exception doesn't get thrown, the code that determines
if the mapping is editable or not gets executed.

Comment 6

[Paul Chen]

Attachment: remove 'about' attributes from <NC:fileExtensions>

Comment 7

[Scott MacGregor]

sr=mscott

Comment 8

[Blake Ross]

r=blake

Comment 9

[Paul Chen]

Fix checked in. Unfortunately, this fixes new profiles only. Other way to fix is
to remove those attributes from your mimeTypes.rdf file in your profile folder.

Comment 10

[shrirang khanzode]

don't see the js error anymore. A Warning "prev sibling is not in or list" 
appers in the console. Hope that does not matter..