clang: Reenable -Wparentheses on mac.

clang: Reenable -Wparentheses on mac.

I disabled it 4 months ago in http://codereview.chromium.org/7046048
and forgot to turn it back on.

BUG=none
TEST=none
TBR=hans

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=105233

[Nico, 2011-10-12 23:38:36]

let's see how many errors this finds… :-/

[commit-bot: I haz the power, 2011-10-12 23:38:45]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/thakis@chromium.org/8253009/1

[commit-bot: I haz the power, 2011-10-13 01:36:59]

Change committed as 105233