This blocks integration tests for tab grid because this is called during setup in ChromeTestCase. 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fe463c15b383607ffb7390e1efabb380a104a369

commit fe463c15b383607ffb7390e1efabb380a104a369
Author: edchin <edchin@chromium.org>
Date: Tue Mar 06 15:56:55 2018

[ios] Basic setup for tab grid egtests

This CL creates a single egtest for tab grid.

To achieve this:
- a new target was setup: ios_chrome_tab_grid_egtests.
- chrome_test_utils was updated to accommodate tab grid.
- creating a new tab and showing BVC was wired up.

Bug:  804542 ,  804585 ,  804587 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Id7e359ef13d1d0b80d845b7787385123f4d42215
Reviewed-on: https://chromium-review.googlesource.com/949609
Commit-Queue: edchin <edchin@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541110}
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/app/tests_fake_hook.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/app/tests_hook.h
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/BUILD.gn
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm
[add] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/tab_grid_egtest.mm
[add] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/tab_grid_egtests_hook.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/tab_grid_view_controller.h
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/tab_grid/tab_grid_view_controller.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/toolbar/adaptive/adaptive_toolbar_eg_tests_hook.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/browser/ui/ui_util.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/test/app/chrome_test_util.mm
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/test/earl_grey/BUILD.gn
[modify] https://crrev.com/fe463c15b383607ffb7390e1efabb380a104a369/ios/chrome/test/earl_grey/eg_tests_hook.mm

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6bed9da4592ae89c091b03760c389a427876dfaa

commit 6bed9da4592ae89c091b03760c389a427876dfaa
Author: edchin <edchin@chromium.org>
Date: Fri Mar 09 16:51:34 2018

[ios] Implement new tab button in tab grid

Bug:  804587 ,  804585 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I108e2c93f2d089133f1f0e1ad065770a032737f1
Reviewed-on: https://chromium-review.googlesource.com/953203
Commit-Queue: edchin <edchin@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542142}
[modify] https://crrev.com/6bed9da4592ae89c091b03760c389a427876dfaa/ios/chrome/browser/ui/tab_grid/BUILD.gn
[modify] https://crrev.com/6bed9da4592ae89c091b03760c389a427876dfaa/ios/chrome/browser/ui/tab_grid/grid_commands.h
[modify] https://crrev.com/6bed9da4592ae89c091b03760c389a427876dfaa/ios/chrome/browser/ui/tab_grid/tab_grid_mediator.mm
[modify] https://crrev.com/6bed9da4592ae89c091b03760c389a427876dfaa/ios/chrome/browser/ui/tab_grid/tab_grid_mediator_unittest.mm
[modify] https://crrev.com/6bed9da4592ae89c091b03760c389a427876dfaa/ios/chrome/browser/ui/tab_grid/tab_grid_view_controller.mm

The NextAction date has arrived: 2018-03-14