Allow icomplete types in scoped_refptr<T>.

Allow icomplete types in scoped_refptr<T>.

This CL hides T::AddRef/Release calls behind a function that is only
accessed during creation / pointer assignment. That allows passing
around scoped_refptrs with incomplete (i.e. forwarded) types.

The downsides are that scoped_refptr is now two pointers wide, and
there is one more level of indirection when calling AddRef / Release.

[DmitrySkiba, 2016-11-01 23:38:27]

The CQ bit was checked by dskiba@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-01 23:39:07]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-01 23:42:06]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-01 23:42:07]

Dry run: Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[DmitrySkiba, 2016-11-02 00:13:53]

The CQ bit was checked by dskiba@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-02 00:14:14]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-02 00:49:31]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-02 00:49:32]

Dry run: Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)

[DmitrySkiba, 2016-11-02 02:09:37]

The CQ bit was checked by dskiba@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-02 02:09:53]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-02 02:52:46]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-02 02:52:47]

Dry run: Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)

[DmitrySkiba, 2016-11-02 05:13:10]

The CQ bit was checked by dskiba@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-02 05:13:25]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[DmitrySkiba, 2016-11-02 06:20:18]

Description was changed from

==========
Allow icomplete types in scoped_refptr<T>.

This CL hides T::AddRef/Release calls behind a function that is only
accessed during creation / pointer assignment. That allows passing
around scoped_refptrs with incomplete (i.e. forwarded) types.
==========

to

==========
Allow icomplete types in scoped_refptr<T>.

This CL hides T::AddRef/Release calls behind a function that is only
accessed during creation / pointer assignment. That allows passing
around scoped_refptrs with incomplete (i.e. forwarded) types.

The downsides are that scoped_refptr is now two pointers wide, and
there is one more level of indirection when calling AddRef / Release.
==========

[commit-bot: I haz the power, 2016-11-02 07:15:55]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-02 07:15:57]

Dry run: This issue passed the CQ dry run.