GitLab

This reverts commit 94218d2c.

Reason for revert: Causing official build test failures.

BUG=865406

Original change's description:
> Make TabLoader responsible for loading all tabs.
> 
> Currently there's an inversion where active tabs in minimized windows don't get
> loaded as they are created. This is an optimization in the occlusion tracking code
> that doesn't calls ReloadIfNecessary unless the window hosting the active tab
> actually becomes visible. Due to this inversion the TabLoader can start loading
> background tabs in the minimized window before the active tab in the minimized
> window is ever loaded.
> 
> Giving TabLoader responsibility to load all tabs fixes this. In the case of
> active and visible tabs whose loads are initiated by the browser this is fine
> because calling ReloadIfNecessary twice is effectively a nop, and the TabLoader
> is already smart enough to track tabs that have started loading for external
> reasons.
> 
> BUG=864725
> 
> Change-Id: I4b86a71470b2cb1a1a9106c4d4d92ee6b18c7284
> Reviewed-on: https://chromium-review.googlesource.com/1141071
> Reviewed-by: Sébastien Marchand <sebmarchand@chromium.org>
> Commit-Queue: Chris Hamilton <chrisha@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#576071}

TBR=chrisha@chromium.org,sebmarchand@chromium.org

Change-Id: Icc2545c1a643042e44b15aa3fb4970045bdba105
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 864725
Reviewed-on: https://chromium-review.googlesource.com/1143565Reviewed-by: Chris Hamilton <chrisha@chromium.org>
Commit-Queue: Chris Hamilton <chrisha@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576494}