Disallow explicit scoped_ptr<T> construction from NULL.

Disallow explicit scoped_ptr<T> construction from NULL.

This matches the behavior of std::unique_ptr<T>, which is the
long-term replacement for scoped_ptr<T>.

BUG=173286
R=jyasskin@chromium.org, mark@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=208773

[dcheng, 2013-06-14 14:48:21]

Hopefully this can land sometime this weekend... Linux/ChromeOS/Mac should be
more or less fixed at this point. Unfortunately, Windows-specific files will
have to be manually handled. With any luck, the CL will be as small as the one
for Mac: https://codereview.chromium.org/16844021/

[dcheng, 2013-06-14 15:20:08]

As it turns out, this is blocked on at least one third_party library, and I
don't expect to land it until sometime next week.

[dcheng, 2013-06-26 18:02:15]

Ping. Mind taking another look now that (almost) all instances have been fixed?

[Jeffrey Yasskin, 2013-06-26 18:13:42]

lgtm if all the trybots build happily.

[Mark Mentovai, 2013-06-26 20:24:28]

LGTM

[dcheng, 2013-06-26 20:29:13]

Committed patchset #4 manually as r208773 (presubmit successful).