Which milestone is this targeting?

I plan to start a field trial from m52. If there are no problem, it could be enabled by default through the server side configurations. But probably, we may need some adjustment for enabling by default, and would be m53 is the milestone for the complete feature.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef

commit 8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef
Author: toyoshim <toyoshim@chromium.org>
Date: Thu May 19 07:24:36 2016

Add a field study to use new reload behavior even on desktops

Now the new reload is used in a field study for Android pull-to-refresh,
but this change introduces it even on desktops as it replaces the
traditional reload operations.

BUG=612701
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/1993603003
Cr-Commit-Position: refs/heads/master@{#394706}

[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/chrome/app/generated_resources.grd
[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/chrome/browser/about_flags.cc
[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/content/browser/frame_host/navigation_controller_impl.cc
[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/content/browser/loader/reload_cache_control_browsertest.cc
[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/content/public/common/content_features.cc
[modify] https://crrev.com/8a956ecdb3d8794d1ddb0a4003e818bfbd19ebef/content/public/common/content_features.h

Set M-52, but it targets to add functionalities to run a field trial.

Remaining works:
 - Make the new reload (RELOAD_MAIN_RESOURCE) work nicely with DevTools. Currently, memory cache change the policy in a wrong way when DevTools is open.

Note: I failed to reproduce this issue on the content browser tests for now, but see a different issue that the third navigation behaves like a usual reload for some unknown reasons only on browser tests.

Not blocking, or blocked on, but just for reference.

BUG=591245

Another note; I quickly checked the study results for desktop, but the impact looks very smaller than I expect. I'd check what makes this difference.

Moving this nonessential bug to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

On mobiles (disabled vs enabled)
200: 76.5% vs 80.3%
304: 9.38% vs 5.56%

On desktops (disabled vs enabled)
200: 83.4% vs 84.5%
304: 5.29% vs 4.42%

The fact is that desktops are getting more 200 results than mobiles are, and it implies the impact for desktops will be smaller than mobiles.

But, I have no idea why 200 rate is so different.

Note: what's wrong on reload w/DevTools

Once cache was disabled in DevTools, all requests never hit memory/http cache even after reenabling it back and closing DevTools.

Note: major change was submitted for m52, and we can enable a field study for m52 and later.

Now, a study was enabled for Canary (m54) and Dev (m53) as 50:50.
I'll enable this for desktop Beta (m52) as 10:10.

One bug was found in the middle of enabling variations test.
https://codereview.chromium.org/2124253002/

How does this impact the metrics?
Would it be pointless to summarize the status for desktop without this CL?

Yes, this won't affect performance as far as I noticed. It's a wrong information on beforeunload event in Chrome UI.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4496d1472533b3c70eddbfd6519e6646bb710ef0

commit 4496d1472533b3c70eddbfd6519e6646bb710ef0
Author: toyoshim <toyoshim@chromium.org>
Date: Thu Jul 07 11:15:53 2016

FrameLoader: Fix NavigationType for FrameLoadTypeReloadMainResource

When I introduced FrameLoadTypeReloadMainResource, this modification
was not applied mistakenly. The right NavigationType for the one
is NavigationTypeReload as is for other reload variants' FrameLoadType.

This results in propagating a wrong is_reload flag to some delegates,
e.g. blink::WebLocalFrameImpl::dispatchBeforeUnloadEvent().

BUG=612701

Review-Url: https://codereview.chromium.org/2124253002
Cr-Commit-Position: refs/heads/master@{#404126}

[modify] https://crrev.com/4496d1472533b3c70eddbfd6519e6646bb710ef0/third_party/WebKit/Source/core/loader/FrameLoader.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/7ae0fd5c2969a7253c23fdad6993898323aba694

commit 7ae0fd5c2969a7253c23fdad6993898323aba694
Author: toyoshim <toyoshim@chromium.org>
Date: Fri Jul 08 09:29:50 2016

Enable NonValidatingReloadOnNormalReload on variations testing

To expand the field study to Beta channel, enable the feature
on variations testing waterfall.

BUG=612701
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2128783002
Cr-Commit-Position: refs/heads/master@{#404321}

[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/content/browser/frame_host/navigator_impl_unittest.cc
[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/content/browser/loader/reload_cache_control_browsertest.cc
[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/content/public/common/content_features.cc
[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/testing/variations/fieldtrial_testing_config_linux.json
[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/testing/variations/fieldtrial_testing_config_mac.json
[modify] https://crrev.com/7ae0fd5c2969a7253c23fdad6993898323aba694/testing/variations/fieldtrial_testing_config_win.json

This issue is Pri-1 but has already been moved once. Lowering the priority and moving to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

It seems the feature is broken a little on the head.
That's completely different from 632358, but it reloads sub-resources even if the feature is enabled (but scroll position behavior is still like being enabled)

I'd run bisect.

Oops, it works if DevTools isn't opened, and that's a kind of known issue.

https://codereview.chromium.org/2274233002/ this will fix our issue too.

 Issue 640687  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0df1d3a01bed974dfa51c3375781f155aed7feea

commit 0df1d3a01bed974dfa51c3375781f155aed7feea
Author: toyoshim <toyoshim@chromium.org>
Date: Fri Sep 09 09:52:48 2016

Navigation: move RestoreType and ReloadType into a separate file

To avoid circular dependency between NavigationController and
NavigationEntry, move RestoreType and ReloadType into a separate file.

This is a refactoring sub-change from crrev.com/2174293002.

BUG=612701
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
TBR=sky@chromium.org, torne@chromium.org

Review-Url: https://codereview.chromium.org/2225343002
Cr-Commit-Position: refs/heads/master@{#417545}

[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/android_webview/browser/icon_helper.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/android_webview/browser/icon_helper.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/android_webview/native/state_serializer.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/android/tab_state.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/chromeos/attestation/platform_verification_dialog.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/chromeos/attestation/platform_verification_dialog.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/devtools/devtools_ui_bindings.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/infobars/infobar_service.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/infobars/infobar_service.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/net/net_error_tab_helper.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/net/net_error_tab_helper.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/net/predictor_tab_helper.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/net/predictor_tab_helper.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/sessions/session_restore_android.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ssl/ssl_browser_tests.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ssl/ssl_error_handler.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ssl/ssl_error_handler.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/android/tab_model/android_live_tab_context.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/bookmarks/bookmark_tab_helper.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/bookmarks/bookmark_tab_helper.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/browser_browsertest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/browser_instant_controller_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/browser_tabrestore.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/omnibox/chrome_omnibox_navigation_observer.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/omnibox/chrome_omnibox_navigation_observer.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/search/search_tab_helper.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/search/search_tab_helper.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/sync/one_click_signin_sync_observer_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/views/session_crashed_bubble_view.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/views/session_crashed_bubble_view.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/webui/extensions/extension_loader_handler.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/webui/extensions/extension_loader_handler.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/chrome/browser/ui/webui/extensions/extension_settings_handler.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/components/favicon/content/content_favicon_driver.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/components/favicon/content/content_favicon_driver.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/android/web_contents_observer_proxy.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/android/web_contents_observer_proxy.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_controller_impl.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_controller_impl.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_controller_impl_browsertest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_controller_impl_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_entry_impl.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_entry_impl.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_entry_impl_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_request.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigation_request.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigator.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigator.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigator_delegate.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigator_impl.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/navigator_impl.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/render_frame_host_manager.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/frame_host/render_frame_host_manager_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/web_contents/aura/overscroll_navigation_overlay_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/web_contents/web_contents_impl.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/web_contents/web_contents_impl.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/web_contents/web_contents_impl_unittest.cc
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/browser/web_contents/web_contents_view_aura_browsertest.cc
[add] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/content_browser.gypi
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/public/browser/navigation_controller.h
[add] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/public/browser/reload_type.h
[add] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/public/browser/restore_type.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/public/browser/web_contents_delegate.h
[modify] https://crrev.com/0df1d3a01bed974dfa51c3375781f155aed7feea/content/public/browser/web_contents_observer.h

@toyoshim: Hey, are there any manual steps to verify the above change ?

Appreciate your response.

Thank you!

What do you want to verify here?
If you meant c27, it does not change anything, it was just for internal code cleanup.

If you are looking at 591245, I'd say this change isn't related to the launching features. 'Blocking' label was misleading here, but this bug also contains changes for the next version beyond the 591245.

On the other hand,  issue 632358  is actually blocking bug for 591245 on desktops. The fix is already merged to beta. Once release channels are refreshed, I'd roll out the feature to the channels step by step.

Note: Desktop feature launch will happen not on m53 but on m54.

It's already launched for 50% users on m54 beta. This will be extended to 100% soon.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c

commit a63c2a63ec73f968a05413c49f1e38dc2c83cd0c
Author: toyoshim <toyoshim@chromium.org>
Date: Thu Sep 29 09:03:26 2016

NonValidatingReload: Monitor reload operations in NavigationControllerImpl

This patch introduces monitoring reload operations.
This is for reporting metrics on subsequent reload
operations as it is in this patch, and will be used
to manage adaptive reload behaviors later.

BUG=612701
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2174293002
Cr-Commit-Position: refs/heads/master@{#421783}

[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/content/browser/frame_host/navigation_controller_impl.cc
[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/content/browser/frame_host/navigation_controller_impl.h
[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/content/browser/frame_host/navigation_controller_impl_browsertest.cc
[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/content/browser/frame_host/navigation_entry_impl.cc
[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/content/browser/frame_host/navigation_entry_impl.h
[modify] https://crrev.com/a63c2a63ec73f968a05413c49f1e38dc2c83cd0c/tools/metrics/histograms/histograms.xml

location.reload() will be enabled at m57.
Once it is enabled by default, I will resume mobile hard-reload work probably at m59.