Fix assertion failure during out-of-order matching

Fix assertion failure during out-of-order matching

The assertion failure occurs in the following sequence:
- Out-of-order matching to n-th item;
- Synchronized matching to (n+m)-th item;
- Out-of-order matching to (n-k)-th item;
- Out-of-order matching to (n+m+l)-th.

The problem is that we only update nextItemToIndex during out-of-order
matching, but not during synchronized matching, causing we tried to
index already copied items (n to n+m).

BUG=526590
TEST=DisplayItemListTest.OutOfOrderNoCrash

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201684

[Xianzhu, 2015-09-02 22:14:49]

wangxianzhu@chromium.org changed reviewers:
+ chrishtr@chromium.org, pdr@chromium.org

[pdr., 2015-09-02 23:13:13]

LGTM

https://codereview.chromium.org/1307653007/diff/1/Source/platform/graphics/pa...
File Source/platform/graphics/paint/DisplayItemListTest.cpp (right):

https://codereview.chromium.org/1307653007/diff/1/Source/platform/graphics/pa...
Source/platform/graphics/paint/DisplayItemListTest.cpp:519: // Test for
crbug.com/526590
No need for this or the comment "// Should not crash", as this test is clean and
easy to understand.

[Xianzhu, 2015-09-02 23:21:44]

https://codereview.chromium.org/1307653007/diff/1/Source/platform/graphics/pa...
File Source/platform/graphics/paint/DisplayItemListTest.cpp (right):

https://codereview.chromium.org/1307653007/diff/1/Source/platform/graphics/pa...
Source/platform/graphics/paint/DisplayItemListTest.cpp:519: // Test for
crbug.com/526590
On 2015/09/02 23:13:12, pdr wrote:
> No need for this or the comment "// Should not crash", as this test is clean
and
> easy to understand.

Done.

[Xianzhu, 2015-09-02 23:21:49]

The CQ bit was checked by wangxianzhu@chromium.org

[Xianzhu, 2015-09-02 23:21:50]

The patchset sent to the CQ was uploaded after l-g-t-m from pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/1307653007/#ps40001
(title: " ")

[commit-bot: I haz the power, 2015-09-02 23:22:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1307653007/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1307653007/40001

[commit-bot: I haz the power, 2015-09-03 00:28:00]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201684