Oilpan: remove too strong start-of-heap-object assert.

Oilpan: remove too strong start-of-heap-object assert.

Remove the assert checking if willObjectBeLazilySwept()'s argument is a
valid reference to the start of a heap object payload. That's too strong
a requirement as the argument might be a mixin pointing some way into
the payload.

Any adjustment needed to get to the object header is taken care of by
isHeapObjectAlive(), which will also check the sanity of the object's
header. Hence, remove the check from willObjectBeLazilySwept().

TBR=oilpan-reviews,haraken
BUG=448392
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=188812

[sof, 2015-01-22 13:38:05]

Please take a look.

My bad, sorry. I should have thought this assert through more carefully and/or
run a complete set of tests. Pre-emptively landing.

[sof, 2015-01-22 13:38:18]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2015-01-22 13:39:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/867623002/1

[commit-bot: I haz the power, 2015-01-22 13:39:47]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=188812

[haraken, 2015-01-22 13:39:55]

On 2015/01/22 13:38:05, sof wrote:
> Please take a look.
> 
> My bad, sorry. I should have thought this assert through more carefully and/or
> run a complete set of tests. Pre-emptively landing.

Thanks for the catch! LGTM.