Make ScrollUpdate LatencyInfo's sequence number less likely to have conflicts

Make ScrollUpdate LatencyInfo's sequence number less likely to have conflicts

BUG=472073
Committed: https://crrev.com/91de260e76a7fab71e5f86749d5eea9ec371663b
Cr-Commit-Position: refs/heads/master@{#325458}

[Yufeng Shen (Slow to review), 2015-04-15 18:53:46]

miletus@chromium.org changed reviewers:
+ skyostil@chromium.org

[Sami, 2015-04-16 10:55:44]

Thanks for fixing this! lgtm with a question.

https://codereview.chromium.org/1089643002/diff/1/cc/trees/latency_info_swap_...
File cc/trees/latency_info_swap_promise_monitor.cc (right):

https://codereview.chromium.org/1089643002/diff/1/cc/trees/latency_info_swap_...
cc/trees/latency_info_swap_promise_monitor.cc:75:
(std::abs(reinterpret_cast<int64>(this)) << 32)) |
Could you replace the abs() with a cast to uint64 before shifting?

[Yufeng Shen (Slow to review), 2015-04-16 15:19:55]

https://codereview.chromium.org/1089643002/diff/1/cc/trees/latency_info_swap_...
File cc/trees/latency_info_swap_promise_monitor.cc (right):

https://codereview.chromium.org/1089643002/diff/1/cc/trees/latency_info_swap_...
cc/trees/latency_info_swap_promise_monitor.cc:75:
(std::abs(reinterpret_cast<int64>(this)) << 32)) |
On 2015/04/16 10:55:44, Sami wrote:
> Could you replace the abs() with a cast to uint64 before shifting?

Done.

[Yufeng Shen (Slow to review), 2015-04-16 15:19:58]

The CQ bit was checked by miletus@chromium.org

[Yufeng Shen (Slow to review), 2015-04-16 15:19:59]

The patchset sent to the CQ was uploaded after l-g-t-m from
skyostil@chromium.org
Link to the patchset: https://codereview.chromium.org/1089643002/#ps20001
(title: "cast to uint64")

[commit-bot: I haz the power, 2015-04-16 15:20:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1089643002/20001

[commit-bot: I haz the power, 2015-04-16 17:00:39]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-04-16 17:01:43]

Patchset 2 (id:??) landed as
https://crrev.com/91de260e76a7fab71e5f86749d5eea9ec371663b
Cr-Commit-Position: refs/heads/master@{#325458}