Remove comparison of address with NULL.

Remove comparison of address with NULL.

Addresses are always non-NULL per spec. This merges a change that has already
been applied to the google-internal version of protobuf.

BUG=381910
TBR=cpu@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=282282

[Reid Kleckner, 2014-07-10 00:39:20]

lgtm

This is so we can roll clang on non-Windows platforms, right?

[Nico, 2014-07-10 00:41:41]

On 2014/07/10 00:39:20, Reid Kleckner wrote:
> lgtm
> 
> This is so we can roll clang on non-Windows platforms, right?

Yes (see BUG= line and the "blocking:" list on that bug :-) )

[Nico, 2014-07-10 01:02:02]

The CQ bit was checked by thakis@chromium.org

[Nico, 2014-07-10 01:03:02]

The CQ bit was unchecked by thakis@chromium.org

[Nico, 2014-07-10 01:03:16]

The CQ bit was checked by thakis@chromium.org

[commit-bot: I haz the power, 2014-07-10 01:04:02]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/thakis@chromium.org/379973003/1

[commit-bot: I haz the power, 2014-07-10 05:17:43]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/mac_chromium_rel/buil...)

[commit-bot: I haz the power, 2014-07-10 08:06:22]

Change committed as 282282