predictors: Call StopPrefetching with an url before redirect.

predictors: Call StopPrefetching with an url before redirect.

It was wrong to use main_frame_url as a parameter for StopPrefetching because
if we have a redirect, StartPrefetching is called with initial_url and
prefetcher manager knows nothing about further redirects. The easiest way to fix
it is to keep using initial_url in all calls to prefetcher manager.
Additionaly, this CL adds a report to prefetch duration histogram in case if we
evict inflight prefetch by timeout.

BUG=631966
Review-Url: https://codereview.chromium.org/2716373002
Cr-Commit-Position: refs/heads/master@{#453605}
Committed: https://chromium.googlesource.com/chromium/src/+/1e620aa2262f96a9cad722d7e5a9266a218ae279

[alexilin, 2017-02-27 15:53:36]

alexilin@chromium.org changed reviewers:
+ lizeb@chromium.org

[alexilin, 2017-02-27 15:53:36]

lizeb, please review this fix!
I mentioned this bug in https://codereview.chromium.org/2719533002

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
File chrome/browser/predictors/resource_prefetch_predictor.cc (left):

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:678: if
(initialization_state_ != INITIALIZED)
This function shouldn't be called before initialization.
Aligned other On* functions as well.

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
File chrome/browser/predictors/resource_prefetch_predictor.cc (right):

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:692:
StopPrefetching(response.navigation_id.main_frame_url);
I'm not sure if we need this fallback.

[Benoit L, 2017-02-27 17:31:19]

lgtm

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
File chrome/browser/predictors/resource_prefetch_predictor.cc (right):

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:692:
StopPrefetching(response.navigation_id.main_frame_url);
On 2017/02/27 15:53:36, alexilin wrote:
> I'm not sure if we need this fallback.

Why are you keeping it?

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:925:
base::TimeTicks::Now() - it->second);
tiny nit: What computing the interval twice? Can you compute it before the if()
above, and use the value here as well?

[alexilin, 2017-02-27 18:15:01]

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
File chrome/browser/predictors/resource_prefetch_predictor.cc (right):

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:692:
StopPrefetching(response.navigation_id.main_frame_url);
On 2017/02/27 17:31:19, Benoit L wrote:
> On 2017/02/27 15:53:36, alexilin wrote:
> > I'm not sure if we need this fallback.
> 
> Why are you keeping it?

Well, if for some reason we don't find an entry in inflight_navigations_ (we
should! but observers are tricky, some races are also possible) we still could
try to stop prefetching using main_frame_url. WDYT?

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:925:
base::TimeTicks::Now() - it->second);
On 2017/02/27 17:31:19, Benoit L wrote:
> tiny nit: What computing the interval twice? Can you compute it before the
if()
> above, and use the value here as well?

Done, thanks.
Actually, this value is always outside of histogram range thus we simply put it
into the last bucket.
For UMA_HISTOGRAM_TIMES max=10s and max_navigation_age=60s by default.

[Benoit L, 2017-02-28 14:26:30]

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
File chrome/browser/predictors/resource_prefetch_predictor.cc (right):

https://codereview.chromium.org/2716373002/diff/1/chrome/browser/predictors/r...
chrome/browser/predictors/resource_prefetch_predictor.cc:692:
StopPrefetching(response.navigation_id.main_frame_url);
On 2017/02/27 18:15:01, alexilin wrote:
> On 2017/02/27 17:31:19, Benoit L wrote:
> > On 2017/02/27 15:53:36, alexilin wrote:
> > > I'm not sure if we need this fallback.
> > 
> > Why are you keeping it?
> 
> Well, if for some reason we don't find an entry in inflight_navigations_ (we
> should! but observers are tricky, some races are also possible) we still could
> try to stop prefetching using main_frame_url. WDYT?

Acknowledged.

[alexilin, 2017-02-28 14:45:04]

The CQ bit was checked by alexilin@chromium.org

[alexilin, 2017-02-28 14:45:04]

The patchset sent to the CQ was uploaded after l-g-t-m from lizeb@chromium.org
Link to the patchset: https://codereview.chromium.org/2716373002/#ps20001
(title: "Fix nit #2.")

[commit-bot: I haz the power, 2017-02-28 14:45:18]

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, 2017-02-28 15:28:54]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1488293104118400,
"parent_rev": "14cea387ce9359e5f9fe3e90c996adf75e092e64", "commit_rev":
"1e620aa2262f96a9cad722d7e5a9266a218ae279"}

[commit-bot: I haz the power, 2017-02-28 15:29:31]

Description was changed from

==========
predictors: Call StopPrefetching with an url before redirect.

It was wrong to use main_frame_url as a parameter for StopPrefetching because
if we have a redirect, StartPrefetching is called with initial_url and
prefetcher manager knows nothing about further redirects. The easiest way to fix
it is to keep using initial_url in all calls to prefetcher manager.
Additionaly, this CL adds a report to prefetch duration histogram in case if we
evict inflight prefetch by timeout.

BUG=631966
==========

to

==========
predictors: Call StopPrefetching with an url before redirect.

It was wrong to use main_frame_url as a parameter for StopPrefetching because
if we have a redirect, StartPrefetching is called with initial_url and
prefetcher manager knows nothing about further redirects. The easiest way to fix
it is to keep using initial_url in all calls to prefetcher manager.
Additionaly, this CL adds a report to prefetch duration histogram in case if we
evict inflight prefetch by timeout.

BUG=631966

Review-Url: https://codereview.chromium.org/2716373002
Cr-Commit-Position: refs/heads/master@{#453605}
Committed:
https://chromium.googlesource.com/chromium/src/+/1e620aa2262f96a9cad722d7e5a9...
==========

[commit-bot: I haz the power, 2017-02-28 15:29:31]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/1e620aa2262f96a9cad722d7e5a9...