Remove measurement of DNS resolution waste from not always performing AF_UNSPEC

Remove measurement of DNS resolution waste from not always performing AF_UNSPEC
lookups. The measurement code has been in long enough to draw conclusions.
This is simply a revert of r151312 and r151710.

BUG=139811
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=175469

[pauljensen, 2013-01-03 15:15:41]

Szymon, PTAL.  I agree with your comment in the bug that the measurement code
has been in long enough to see the benefit is negligible.

[pauljensen, 2013-01-07 20:12:56]

ping

[szym, 2013-01-07 20:23:57]

On 2013/01/07 20:12:56, pauljensen wrote:
> ping

LGTM.

Spent some time trying to diagnose how come the new PAC script only requires
dnsResolve for a small fraction of hosts. It appears that only single-label
names and names matching corp-specific patterns lead to dnsResolve, which
explains why the observed waste is minimal in our network, but the global
results from your measurement suggest that other PAC scripts hardly ever invoke
dnsResolve.

[commit-bot: I haz the power, 2013-01-07 20:28:55]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pauljensen@chromium.org/11734020/1

[commit-bot: I haz the power, 2013-01-07 21:25:52]

Retried try job too often on win_rel for step(s) browser_tests,
content_unittests, ipc_tests, media_unittests, net_unittests, ppapi_unittests,
remoting_unittests, sync_unit_tests, unit_tests

[commit-bot: I haz the power, 2013-01-07 22:40:04]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pauljensen@chromium.org/11734020/1

[commit-bot: I haz the power, 2013-01-08 02:13:21]

Change committed as 175469