GitLab

This reverts commit a61d2bb4.

Reason for revert:

Findit (https://goo.gl/kROfz5) identified CL at revision 612980 as the
culprit for flakes in the build cycles as shown on:
https://findit-for-me.appspot.com/waterfall/flake/flake-culprit?key=ag9zfmZpbmRpdC1mb3ItbWVyQwsSDEZsYWtlQ3VscHJpdCIxY2hyb21pdW0vYTYxZDJiYjQzMDRkZjgyOGRhNjBhZjA3ZjBiMDVmMzNlNDlmZDE4Zgw

Sample Failed Build: https://ci.chromium.org/buildbot/chromium.chromiumos/linux-chromeos-dbg/9304

Sample Failed Step: sync_integration_tests

Sample Flaky Test: SingleClientSessionsSyncTest.NavigateThenCloseTabThenOpenTab

Original change's description:
> Reland "Avoid recycling sync tabs if commit pending"
> 
> This is a reland of 62414cfc
> 
> Test improved to avoid flakes.
> 
> Original change's description:
> > Avoid recycling sync tabs if commit pending
> >
> > When a tab is closed, it's possible that the corresponding history
> > hasn't been committed yet, and hence there is a risk that synced history
> > is lost if the entity is recycled (for another tab that is opened).
> >
> > In this patch, and behind a feature toggle, this issue is prevented by
> > *not* freeing tab nodes while the sync entity is unsynced. Old tabs are
> > excluded from this (to avoid problems with expired history) and a max
> > cap is also introduced to the number of tabs in this state, in order to
> > avoid memory regressions.
> >
> > Bug: 882489
> > Change-Id: I6dd796642f9553f2713a0814731897a4ffb13f0b
> > Reviewed-on: https://chromium-review.googlesource.com/c/1356541
> > Commit-Queue: Mikel Astiz <mastiz@chromium.org>
> > Reviewed-by: Marc Treib <treib@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#612971}
> 
> TBR=treib@chromium.org
> 
> Bug: 882489
> Change-Id: Ib3f3ff9e4d620512435d9b22ba7b2c338f92203f
> Reviewed-on: https://chromium-review.googlesource.com/c/1357086
> Reviewed-by: Mikel Astiz <mastiz@chromium.org>
> Commit-Queue: Mikel Astiz <mastiz@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#612980}

Change-Id: I69bf304dc196b29f2b6ccf5f15ff8dd77ca7d610
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 882489, 910947
Reviewed-on: https://chromium-review.googlesource.com/c/1357826
Cr-Commit-Position: refs/heads/master@{#612982}