Add missing buffer reorg on Deque buffer expansion.

Add missing buffer reorg on Deque buffer expansion.

If a deque's buffer is expanded in place and that buffer contains items
at either buffer ends when that happens, make sure the end segment is moved
up to the end of the expanded buffer, along with adjusting the start
index.

R=thakis,haraken
BUG=445352
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=187800

[sof, 2014-12-30 22:40:52]

sigbjornf@opera.com changed reviewers:
+ erik.corry@gmail.com, jochen@chromium.org, oilpan-reviews@chromium.org,
thakis@chromium.org

[sof, 2014-12-30 22:40:53]

Please take a look

The lack of buffer readjustment on expansion causes some havoc with
webdatabase/'s transaction queue, as reported on the associated bug.

(Longer reviewer list than usual, added in the hope that at least one of you is
around this week.. :) )

[Nico, 2014-12-31 01:21:38]

Sneaky. lgtm, but I feel the comments don't add too much information and make it
harder to see the symmetry to the similar bit further down in the function. (For
the same reason, I'd probably do if/else here instead of if and early return,
even though I almost always do the latter.)

https://codereview.chromium.org/835453002/diff/1/Source/platform/heap/HeapTes...
File Source/platform/heap/HeapTest.cpp (right):

https://codereview.chromium.org/835453002/diff/1/Source/platform/heap/HeapTes...
Source/platform/heap/HeapTest.cpp:5358: // Append a sequence, bringing about
expansion of the
of the…?

[haraken, 2014-12-31 01:47:58]

LGTM

[sof, 2014-12-31 05:18:16]

Thanks both for the quick reviews.

I scaled/removed the Deque.h comment to be consistent with context and overall
comment use in that file. The original comment was added to "talk" myself
through the correctness of the change as much as anything, I'd say.

[sof, 2014-12-31 05:18:31]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2014-12-31 05:18:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/835453002/20001

[commit-bot: I haz the power, 2014-12-31 07:38:51]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=187800