Use const_iterator while iterating const std::set<>&

Use const_iterator while iterating const std::set<>&

BUG=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=202491

[kouhei (in TOK), 2013-05-27 01:50:05]

nduca: Would you review this patch? Not in a hurry.

I found this while force-enabling tracing_ui.cc compile on Android. Although the
code compiles as std::set<T>::iterator == std::set<T>::const_iterator in gcc, I
think this code is against the C++ STL spec.

[kouhei (in TOK), 2013-05-27 01:51:46]

+fix reviewers, cc

nduca: Would you review this patch? Not in a hurry.

[nduca, 2013-05-27 08:48:51]

lgtm

[kouhei (in TOK), 2013-05-27 08:54:41]

Thanks for review!

[commit-bot: I haz the power, 2013-05-27 08:54:53]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kouhei@chromium.org/15714004/1

[commit-bot: I haz the power, 2013-05-27 12:46:23]

Retried try job too often on win_rel for step(s) browser_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-05-28 00:17:42]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kouhei@chromium.org/15714004/1

[commit-bot: I haz the power, 2013-05-28 03:15:54]

Change committed as 202491