Add <code> to sensitive tags in collapse_whitespace_filter.

[Dreamsorcerer]

Fixes #1772

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[jmarantz]

very cool. Could you also add a test in collapse_whitespace_filter_test.cc? The pattern should be fairly obvious there.

[googlebot]

CLAs look good, thanks!

[oschaaf]

Nice, thanks!

[jmarantz]

@oschaaf do you know why CI is failing? I re-started it once, but both attempts ended in:

ld/apache/incubator-pagespeed-mod/third_party/giflib/src'...
No output has been received in the last 10m0s, this potentially indicates a stalled build or something wrong with the build itself.
Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#Build-times-out-because-no-output-was-received
The build has been terminated

I'll try a third time. If that fails we can I guess patch/build/test and then merge, but I wanted to see if you thought the CI was failing like this generally and if we should so something about that.

[oschaaf]

@jmarantz I noticed the same with another PR lately, but have not investigated yet. perhaps one of the dependencies broke, I’ll take a look later today

[oschaaf]

So the test failed on But do proxy content if the Content-Type header is present..
This was very reproducible because a required script that serves test responses was not running on modpagespeed.com. I recently rebuild the machine from scrap to simplify some things, and forgot all about that script. Restarted the CI job, expect this to be fixed.
(Though sometimes CI may still flake because of the tests requiring an amount of time that is pretty close to the timeout limit.)

[jmarantz]

We should separately address our CI issues. In the meantime, I patched this change and confirmed it passes its own test...running checkin.make now. Shall we just go ahead & merge?

[oschaaf]

@jmarantz +1 for merging

With regard to giflib, that started failing when sourceforge starting migrating
datacenters. I already attempted a fix [1] earlier because the previous location started
responding with 404 ..
But apparently the git repo we now point to times out every now and then, ugh.

[1] 8196fc7