Allow Objective-C interfaces in //base/ios

Allow Objective-C interfaces in //base/ios

Objective-C interfaces are disallowed in base because of a bug related
to plugins.
There are no plugins on iOS, and //base/ios is not compiled for other
platforms.

Committed: https://crrev.com/114a60b29b034a2d658738aae08ec889d6a6b866
Cr-Commit-Position: refs/heads/master@{#303007}

[droger, 2014-11-05 16:34:08]

droger@chromium.org changed reviewers:
+ thakis@chromium.org

[droger, 2014-11-05 16:36:08]

The motivation for this change is that I would like to upstream our WeakNSObject
class (which is roughly equivalent to WeakPtr).

I am not sure if WeakNSObject would be useful for mac as well, in which case an
alternative is to rewrite WeakNSObject to not use interfaces (which is possible,
but makes the code a little messier).

[stuartmorgan, 2014-11-05 16:50:49]

On 2014/11/05 16:36:08, droger wrote:
> I am not sure if WeakNSObject would be useful for mac as well, in which case
an
> alternative is to rewrite WeakNSObject to not use interfaces (which is
possible,
> but makes the code a little messier).

My vote would be to leave it iOS-only for now until/unless someone has a
demonstrated need for it on Mac. There's a reasonable chance that it'll go away
entirely before that (due to ARC adoption on iOS, which is still on my roadmap).

[Nico, 2014-11-05 17:05:45]

lgtm if you folks want to do this.

I weakly feel that making it harder to share code between ios and mac might be
bad down the road. If this class is going away eventually and/or can be
rewritten without @interfaces without much work…but it's just a hunch, so go
ahead if you want. Even if @interfaces in base/ios turn out to be annoying in
the future for some reason, there probably won't be many and it won't be too
hard to change it then.

[droger, 2014-11-06 10:01:08]

I'd be in favor of landing this presubmit change.
For WeakNSObject, I don't have a strong opinion, I would suggest that we first
put it in ios/ with the interfaces, and move it to mac/ later if there is a
need.

I already have a CL to remove the interfaces if needed
(https://chromereviews.googleplex.com/116637013/).

[droger, 2014-11-06 10:01:58]

The CQ bit was checked by droger@chromium.org

[commit-bot: I haz the power, 2014-11-06 10:02:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/708513002/1

[commit-bot: I haz the power, 2014-11-06 11:06:59]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-06 11:07:39]

Patchset 1 (id:??) landed as
https://crrev.com/114a60b29b034a2d658738aae08ec889d6a6b866
Cr-Commit-Position: refs/heads/master@{#303007}