Document weak pointer factory constructor requirement.

Document weak pointer factory constructor requirement.

Committed: https://crrev.com/d5144064af15ce8e24589891c326400a43c27ce0
Cr-Commit-Position: refs/heads/master@{#348966}

[scheib, 2015-09-11 18:29:48]

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

[Nico, 2015-09-11 18:41:40]

lgtm, but:

https://codereview.chromium.org/1336763005/diff/1/base/memory/weak_ptr.h
File base/memory/weak_ptr.h (right):

https://codereview.chromium.org/1336763005/diff/1/base/memory/weak_ptr.h#newc...
base/memory/weak_ptr.h:19: //    Controller() : weak_factory_(this) {}
It's not always `this`, is it? It's just the pointer the weak pointer handed out
by the factor points to, right? It could also be a pointer to e.g. a field of
this.

[scheib, 2015-09-11 19:40:29]

https://codereview.chromium.org/1336763005/diff/1/base/memory/weak_ptr.h
File base/memory/weak_ptr.h (right):

https://codereview.chromium.org/1336763005/diff/1/base/memory/weak_ptr.h#newc...
base/memory/weak_ptr.h:19: //    Controller() : weak_factory_(this) {}
On 2015/09/11 18:41:39, Nico wrote:
> It's not always `this`, is it? It's just the pointer the weak pointer handed
out
> by the factor points to, right? It could also be a pointer to e.g. a field of
> this.

True, but in this example the factory vends Controller pointers.

[Nico, 2015-09-15 02:46:29]

(wanna cq this?)

[scheib, 2015-09-15 17:30:00]

The CQ bit was checked by scheib@chromium.org

[commit-bot: I haz the power, 2015-09-15 17:31:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1336763005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1336763005/1

[commit-bot: I haz the power, 2015-09-15 19:53:24]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-15 19:54:04]

Patchset 1 (id:??) landed as
https://crrev.com/d5144064af15ce8e24589891c326400a43c27ce0
Cr-Commit-Position: refs/heads/master@{#348966}

[commit-bot: I haz the power, 2015-09-23 12:48:26]

Patchset 1 (id:??) landed as
https://crrev.com/d5144064af15ce8e24589891c326400a43c27ce0
Cr-Commit-Position: refs/heads/master@{#348966}