WeakNodeMap should have an ASSERT for node in WeakNodeMap::put()

WeakNodeMap should have an ASSERT for node in WeakNodeMap::put()

WeakNodeMap holds trace Ids to corresponding node pointers. Having a null value for the node would be logically incorrect and the ASSERT(!m_nodeToValue.contains(node)); would trigger for the subsequent calls if we allow the NULL values. The callsite should ensure that the values for node pointers are indeed non-NULL.

BUG=390510
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177370

[vivekg, 2014-07-01 12:24:43]

PTAL, thank you!

[eseidel, 2014-07-02 05:39:26]

Could you explain why in the description?  I presume because null is not a valid
argument to WTF containers?

[vivekg, 2014-07-02 05:46:35]

On 2014/07/02 05:39:26, eseidel wrote:
> Could you explain why in the description?  I presume because null is not a
valid
> argument to WTF containers?

Updated the description:
WeakNodeMap holds trace Ids to corresponding node pointers. Having a null value
for the node would be logically incorrect and the
ASSERT(!m_nodeToValue.contains(node)); would trigger for the subsequent calls if
we allow the NULL values. The callsite should ensure that the values for node
pointers are indeed non-NULL.

[eseidel, 2014-07-02 05:47:11]

lgtm

[commit-bot: I haz the power, 2014-07-02 05:47:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/vivek.vg@samsung.com/365633003/1

[commit-bot: I haz the power, 2014-07-02 06:29:15]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/mac_gpu_triggered...)

[caseq, 2014-07-02 10:03:09]

I think the only value ASSERT() adds here is documenting our expectations, since
in case put() is passed NULL, we're bound to crash upon null dereference in line
79 and the cause of the crash would be pretty evident.

OTOH, as far as documenting expectation goes, I think making node a reference,
not pointer, is better.

[commit-bot: I haz the power, 2014-07-02 13:02:37]

Change committed as 177370