Use scoped_ptr::Pass instead of scoped_ptr::PassAs<T>.

Use scoped_ptr::Pass instead of scoped_ptr::PassAs<T>.

Also convert a few explicit invocations of the default scoped_ptr
ctor to just use nullptr instead.

BUG=423621
Committed: https://crrev.com/84b60296949265b42e9b54937563be58fdcc0b8c
Cr-Commit-Position: refs/heads/master@{#299709}

[dcheng, 2014-10-15 04:48:06]

dcheng@chromium.org changed reviewers:
+ danakj@chromium.org

[danakj, 2014-10-15 17:20:08]

Can you mention the nullptr changes in the patch description?

LGTM

https://codereview.chromium.org/655003004/diff/1/base/metrics/histogram.cc
File base/metrics/histogram.cc (right):

https://codereview.chromium.org/655003004/diff/1/base/metrics/histogram.cc#ne...
base/metrics/histogram.cc:372: return samples;
Oh that's cool I didn't realize we can do that now.

[dcheng, 2014-10-15 17:29:56]

On 2014/10/15 at 17:20:08, danakj wrote:
> Can you mention the nullptr changes in the patch description?
> 

Done.

> LGTM
> 
> https://codereview.chromium.org/655003004/diff/1/base/metrics/histogram.cc
> File base/metrics/histogram.cc (right):
> 
>
https://codereview.chromium.org/655003004/diff/1/base/metrics/histogram.cc#ne...
> base/metrics/histogram.cc:372: return samples;
> Oh that's cool I didn't realize we can do that now.

The cases we can do this are limited, but yay, copy elision!

[dcheng, 2014-10-15 17:30:02]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2014-10-15 17:31:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/655003004/1

[commit-bot: I haz the power, 2014-10-15 17:48:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-15 17:48:42]

Patchset 1 (id:??) landed as
https://crrev.com/84b60296949265b42e9b54937563be58fdcc0b8c
Cr-Commit-Position: refs/heads/master@{#299709}