Refactor: Clear m_axObjectCache when AXObject detaches

Refactor: Clear m_axObjectCache when AXObject detaches

Clear m_axObjectCache when AXObject detaches so we don't keep a stale pointer.
Also remove m_detached and use m_axObjectCache instead.
Also added an ASSERT to axObjectCache() getter so we can detect when we try to access the cache from a detached AXObject.

BUG=None

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197527

[haraken, 2015-06-11 11:14:35]

haraken@chromium.org changed reviewers:
+ haraken@chromium.org

[haraken, 2015-06-11 11:14:36]

LGTM

[dmazzoni, 2015-06-11 16:19:47]

dmazzoni@chromium.org changed reviewers:
+ dmazzoni@chromium.org

[dmazzoni, 2015-06-11 16:19:47]

lgtm with one suggestion.

Could you add a null check to *every* place axObjectCache() is called as part of
this change? There are a few places where it's not checked and I'd rather err on
the safe side rather than relying on assumptions that are true now.

[keishi, 2015-06-19 12:28:07]

On 2015/06/11 16:19:47, dmazzoni wrote:
> lgtm with one suggestion.
> 
> Could you add a null check to *every* place axObjectCache() is called as part
of
> this change? There are a few places where it's not checked and I'd rather err
on
> the safe side rather than relying on assumptions that are true now.

Added an ASSERT to axObjectCache() getter so we can detect when we try to access
the cache from a detached AXObject.

[keishi, 2015-06-20 04:47:10]

The CQ bit was checked by keishi@chromium.org

[keishi, 2015-06-20 04:47:10]

The patchset sent to the CQ was uploaded after l-g-t-m from
haraken@chromium.org, dmazzoni@chromium.org
Link to the patchset: https://codereview.chromium.org/1175533004/#ps20001
(title: "Added ASSERT")

[commit-bot: I haz the power, 2015-06-20 04:47:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1175533004/20001

[commit-bot: I haz the power, 2015-06-20 06:13:00]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197527