Oilpan: Validate pointers stored in Member

Oilpan: Validate pointers stored in Member

This CL adds checkPointer() to all pointer updates of Member.
The checkPointer() verifies that the pointer is either of:

- nullptr
- a special value to represent a deleted entry of a HashTable
- a pointer to an on-heap object

BUG=475801
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=196287

[haraken, 2015-05-21 11:29:35]

haraken@chromium.org changed reviewers:
+ keishi@chromium.org, oilpan-reviews@chromium.org

[haraken, 2015-05-21 11:29:36]

Not yet for review.

The ASSERT added in this CL is correct but the ASSERT unacceptably slows down
testing. I need to look into the performance issue.

[haraken, 2015-05-26 13:27:53]

This CL is now ready for review, but I understand that the ASSERT is doing
something ugly...

Overall, what I want to verify is that Member<>, Persistent<> and
CrossThreadPersistent<> hold a reference to a traceable object.

https://codereview.chromium.org/1149903004/diff/40001/Source/platform/heap/Ha...
File Source/platform/heap/Handle.h (right):

https://codereview.chromium.org/1149903004/diff/40001/Source/platform/heap/Ha...
Source/platform/heap/Handle.h:683: // TODO(haraken): What we really want to
check here is that the pointer

I welcome any idea to fix this TODO.

[haraken, 2015-06-01 11:08:49]

Fixed failing tests. The TODO in the CL is a bit unfortunate, but it seems
better to land this verification than not doing anything.

keishi-san: PTAL.

[keishi, 2015-06-02 02:43:36]

lgtm

[haraken, 2015-06-02 04:37:02]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2015-06-02 04:37:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1149903004/120001

[haraken, 2015-06-02 04:37:29]

Thanks for review! The bots are green, so let me land this.

[commit-bot: I haz the power, 2015-06-02 06:08:34]

Committed patchset #7 (id:120001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=196287