service worker: Optimize response header creation.

service worker: Optimize response header creation.

HttpResponseHeaders::AddHeader has O(n^2) performance. Avoid using it.

I verified on Linux that constructing the headers from a 
ServiceWorkerHeaderMap of 1000 headers goes from ~500ms to <1ms.

BUG=687230
Review-Url: https://codereview.chromium.org/2690333003
Cr-Commit-Position: refs/heads/master@{#450563}
Committed: https://chromium.googlesource.com/chromium/src/+/cd398136c4992574a2161d68acb39c716095eedd

[falken, 2017-02-14 07:23:02]

Description was changed from

==========
service worker: Optimize response header creation.

HttpResponseHeaders::AddHeader has O(n^2) performance. Avoid using it.

BUG=687230
==========

to

==========
service worker: Optimize response header creation.

HttpResponseHeaders::AddHeader has O(n^2) performance. Avoid using it.

I verified on Linux that constructing the headers from a 
ServiceWorkerHeaderMap of 1000 headers goes from ~500ms to <1ms.

BUG=687230
==========

[falken, 2017-02-14 07:23:48]

falken@chromium.org changed reviewers:
+ horo@chromium.org

[falken, 2017-02-14 07:23:48]

horo: ptal

[falken, 2017-02-14 08:14:27]

The CQ bit was checked by falken@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-02-14 08:14:51]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-02-14 09:42:27]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-02-14 09:42:28]

Dry run: This issue passed the CQ dry run.

[falken, 2017-02-14 12:53:14]

falken@chromium.org changed reviewers:
+ xunjieli@chromium.org

[falken, 2017-02-14 12:53:14]

xunjieli: ptal

[xunjieli, 2017-02-14 17:09:58]

lgtm. thanks for the fix.

https://codereview.chromium.org/2690333003/diff/1/content/browser/service_wor...
File content/browser/service_worker/service_worker_url_request_job.cc (right):

https://codereview.chromium.org/2690333003/diff/1/content/browser/service_wor...
content/browser/service_worker/service_worker_url_request_job.cc:684: for (auto
it = headers.begin(); it != headers.end(); ++it) {
nit: 

for (const auto& item : headers) {

[horo, 2017-02-14 22:25:28]

lgtm

[falken, 2017-02-15 00:39:39]

> thanks for the fix.
Thank you for pointing out the bug!

https://codereview.chromium.org/2690333003/diff/1/content/browser/service_wor...
File content/browser/service_worker/service_worker_url_request_job.cc (right):

https://codereview.chromium.org/2690333003/diff/1/content/browser/service_wor...
content/browser/service_worker/service_worker_url_request_job.cc:684: for (auto
it = headers.begin(); it != headers.end(); ++it) {
On 2017/02/14 17:09:58, xunjieli wrote:
> nit: 
> 
> for (const auto& item : headers) {

Done.

[falken, 2017-02-15 00:42:11]

The CQ bit was checked by falken@chromium.org

[falken, 2017-02-15 00:42:12]

The patchset sent to the CQ was uploaded after l-g-t-m from horo@chromium.org,
xunjieli@chromium.org
Link to the patchset: https://codereview.chromium.org/2690333003/#ps20001
(title: "fix auto")

[commit-bot: I haz the power, 2017-02-15 00:43:51]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-02-15 05:37:12]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1487119331523980,
"parent_rev": "f3a83d8bd18c6a3672c99705b96cff4a8e6b5366", "commit_rev":
"cd398136c4992574a2161d68acb39c716095eedd"}

[commit-bot: I haz the power, 2017-02-15 05:38:45]

Description was changed from

==========
service worker: Optimize response header creation.

HttpResponseHeaders::AddHeader has O(n^2) performance. Avoid using it.

I verified on Linux that constructing the headers from a 
ServiceWorkerHeaderMap of 1000 headers goes from ~500ms to <1ms.

BUG=687230
==========

to

==========
service worker: Optimize response header creation.

HttpResponseHeaders::AddHeader has O(n^2) performance. Avoid using it.

I verified on Linux that constructing the headers from a 
ServiceWorkerHeaderMap of 1000 headers goes from ~500ms to <1ms.

BUG=687230

Review-Url: https://codereview.chromium.org/2690333003
Cr-Commit-Position: refs/heads/master@{#450563}
Committed:
https://chromium.googlesource.com/chromium/src/+/cd398136c4992574a2161d68acb3...
==========

[commit-bot: I haz the power, 2017-02-15 05:38:46]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/cd398136c4992574a2161d68acb3...