Fix WebsitePreference::compareTo.

Fix WebsitePreference::compareTo.

Should not return constant when compared against object of class Preference.

BUG=450862
Committed: https://crrev.com/ac1aaf963cfedf830afce10e2bfe1a9504bd49d3
Cr-Commit-Position: refs/heads/master@{#314135}

[Finnur, 2015-01-26 14:13:19]

finnur@chromium.org changed reviewers:
+ mnaganov@chromium.org

[mnaganov (inactive), 2015-01-26 14:14:47]

LGTM, thanks!

[Finnur, 2015-01-26 14:15:21]

The CQ bit was checked by finnur@chromium.org

[commit-bot: I haz the power, 2015-01-26 14:15:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/875003002/1

[Finnur, 2015-01-26 14:18:40]

The CQ bit was unchecked by finnur@chromium.org

[Finnur, 2015-01-26 14:19:48]

finnur@chromium.org changed reviewers:
+ newt@chromium.org

[Finnur, 2015-01-26 14:20:00]

Need OWNERS approval from Newton.

[newt (away), 2015-01-26 18:45:46]

lgtm

[newt (away), 2015-01-26 18:49:07]

On 2015/01/26 18:45:46, newt wrote:
> lgtm

Were you able to repro the failure? Or is this a speculative fix?

[Finnur, 2015-01-27 10:04:03]

I was able to repro. 

Basically, create a blank Preference object p and a any kind of
WebsitePreference object w.

The result:
p.compareTo(w) is hard-coded (see Preference::compareTo) to return 1 because
title of p is null.
w.compareTo(p) is hard-coded (see WebsitePreference::compareTo)to return 1
because p is not of the right type. And that's basically the problem in a
nutshell.

By asking the super to compare, we make sure the two are evaluated on equal
grounds (by title, basically).

[Finnur, 2015-01-27 10:04:54]

The CQ bit was checked by finnur@chromium.org

[commit-bot: I haz the power, 2015-01-27 10:05:23]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/875003002/1

[commit-bot: I haz the power, 2015-01-27 10:05:36]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-01-27 10:05:36]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[Finnur, 2015-02-02 12:33:43]

The CQ bit was checked by finnur@chromium.org

[commit-bot: I haz the power, 2015-02-02 12:34:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/875003002/20001

[commit-bot: I haz the power, 2015-02-02 13:35:07]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-02 13:36:15]

Patchset 2 (id:??) landed as
https://crrev.com/ac1aaf963cfedf830afce10e2bfe1a9504bd49d3
Cr-Commit-Position: refs/heads/master@{#314135}