3719: 2.0.12 fails to render tables in Markdown according to the Markdown reference guide

jr***@yelp**** (Google Code) (Is this you? Claim this profile.) 
What version are you running?

2.0.12


What's the URL of the page containing the problem?

See screenshots


What steps will reproduce the problem?
1. Paste the example table from the markdown reference guide into a new review request textarea field:

Header | Header | Header
-------|--------|-------
Cell   | Cell   | Cell
Cell   | Cell   | Cell

2. Allow reviewboard to render the text

What is the expected output? What do you see instead?

Expected: See screenshot 2.0.11.png
Actual: See screenshot 2.0.12.png

What operating system are you using? What browser?

RB is installed on Ubuntu Trusty. I am viewing RB via chromium.
#1 ran***@circularre*********** (Google Code) (Is this you? Claim this profile.) 
I'm seeing this as well in 2.0.13. Server is linux. I'm running Firefox 38.0.5 in Windows 7 64 bit.
#2 ran***@circularre*********** (Google Code) (Is this you? Claim this profile.) 
The tables are properly formatted in the email notifications. They render as tables (the 2.0.11.png image above) when viewed in Outlook and in Outlook Web Access (IE and Firefox).

The same table is displayed unformatted (the 2.0.12.png image) on reviewboard web sites (in Firefox, IE and Chrome).