bug fix 760240 - Change docs/* 404's into redirects to the create page

[darkwing]

https://bugzilla.mozilla.org/show_bug.cgi?id=760240

[lmorchard]

Hmm, one nit I'm seeing:

• I go to non-existent page http://developer-dev.mozilla.org/en-US/docs/CSS/Foobar
• Redirect to http://developer-dev.mozilla.org/en-US/docs/new?slug=Foobar&parent=1320
• Title is empty (expected it to be populated by same as slug)
• When I edit the title, the slug disappears and changes to what I'm editing

That last part is of course just how title-slugification works, but it seems like I have to repeat myself and might change the 404'd slug in the URL. And, since that slug presumably came from a link I clicked on, I might change the slug to something different than I started with, and so create a page that doesn't resolve the 404 that I clicked into.

I don't think we should do anything like prevent slug editing if the user really wants to do that, but getting the title populated could help prevent mistakes in creating pages from 404 links.

[lmorchard]

Tests pass, things work fine beyond my nitpick

[darkwing]

Good point Les, updated.

[lmorchard]

Tests still pass, title population works. But, one more nit (sorry!):

• All good, visiting:
  • http://developer-dev.mozilla.org/en-US/docs/CSS
• Visiting this results in an attempt to create a page with an empty slug (note trailing slash):
  • http://developer-dev.mozilla.org/en-US/docs/CSS/

Probably a rare case, but this instead should probably be a redirect to CSS

[darkwing]

Added code to remove the trailing slashes and redirect as necessary to prevent unwanted document creations.

[lmorchard]

One more nitpick... I can't find any more nitpicks. Works for me, tests pass.