mod_pagespeed should strip query-params for pagespeed resources before cache lookup

[GoogleCodeExporter]

What steps will reproduce the problem?
1. appeared randomly after a long period (weeks) running mod_pagespeed 
2. the following in HTML document HEAD (multiple websites):

  <link rel="stylesheet" type="text/css" href="http://resources.chirp.com.au/form_formatting.css">
  <link rel="stylesheet" type="text/css" href="http://resources.chirp.com.au/table_formatting.css">

3. may be triggered by requests from webcache.googleusercontent.com

What is the expected output?
e.g.
  <link rel="stylesheet" type="text/css" href="http://resources.chirp.com.au/form_formatting.css+gday_formatting.css.pagespeed.cc.2_ZYbhEFlY.css">

What do you see instead?
e.g.
  <link rel="stylesheet" type="text/css" href="http://resources.chirp.com.au/form_formatting.css+table_formatting.css.pagespeed.cc.p2rjIj5pXZ.css%22">

(the extra '%22' in the address is causing the CSS not to be read by the 
browser)

First sign in apache logs was 24 hours ago:

68.209.129.173 - - [20/Jan/2011:07:48:19 +0100] "GET 
/form_formatting.css+table_formatting.css.pagespeed.cc.Er27ofunUS.css%22 
HTTP/1.1" 200 1871 
"http://webcache.googleusercontent.com/search?q=cache:FHpe41nOywQJ:www.the-art-o
f-web.com/html/character-codes/+javascript+character+%26raquo%3B&cd=9&hl=en&ct=c
lnk&gl=us" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; 
SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.5.30729; .NET CLR 
3.0.30729; .NET4.0C)"

which then propagated for 20 minutes (total of 63 occurrences).

Then today it started again, around 2 hours ago, and is continuing. The first 
instance was:

89.241.2.254 - - [21/Jan/2011:14:55:08 +0100] "GET 
/form_formatting.css+table_formatting.css.pagespeed.cc.Er27ofunUS.css%22 
HTTP/1.1" 200 1871 
"http://webcache.googleusercontent.com/search?q=cache:auh-6vJ3x9wJ:www.the-art-o
f-web.com/css/bordercollapse/1/+border-collapse+separate&cd=1&hl=en&ct=clnk&clie
nt=firefox-a" "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.12) 
Gecko/20101027 Fedora/3.6.12-1.fc13 Firefox/3.6.12"

and the most recent:

94.34.40.110 - - [21/Jan/2011:16:14:37 +0100] "GET 
/form_formatting.css+table_formatting.css.pagespeed.cc.p2rjIj5pXZ.css%22 
HTTP/1.1" 200 1871 "http://www.the-art-of-web.com/css/border-radius/" 
"Mozilla/5.0 (X11; U; Linux i686; it; rv:1.9.2.13) Gecko/20101206 Ubuntu/10.10 
(maverick) Firefox/3.6.13"

So far today, 362 occurrences and counting.

No signs in preceding one week of log files and we haven't notices a similar 
problem in the last couple of months.


What version of the product are you using? 0.9.14.6-r358

On what operating system? Debian GNU/Linux

Which version of Apache? 2.2.9

Which MPM?

  ModPagespeedDisableFilters inline_css,inline_javascript
  ModPagespeedEnableFilters move_css_to_head
  ModPagespeedEnableFilters rewrite_css,rewrite_javascript
  ModPagespeedEnableFilters outline_css,outline_javascript


Please provide any additional information below, especially a URL or an
HTML file that exhibits the problem.

Occurring on multiple pages across multiple websites on the same server.
Including: http://www.the-art-of-web.com/system/mod-pagespeed/

Original issue reported on code.google.com by [email protected] on 21 Jan 2011 at 3:17