The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e56e2bba7ccd18b1da071171909f326924eb0230

commit e56e2bba7ccd18b1da071171909f326924eb0230
Author: Menglu Huang <huangml@chromium.org>
Date: Tue Feb 20 07:28:32 2018

Implement iOS test sharding with multiple simulators on test_runner.

Details in doc:
https://docs.google.com/document/d/1QaAZgmYuEImL1wAYJQxPcbex-fPLVd3rx8oMMKIgZX8/edit#

Bug:  808267 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I55fc27fcf31120a7c9d39e8953f72a39dd6394a7
Reviewed-on: https://chromium-review.googlesource.com/917309
Commit-Queue: Menglu Huang <huangml@chromium.org>
Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537731}
[modify] https://crrev.com/e56e2bba7ccd18b1da071171909f326924eb0230/ios/build/bots/scripts/run.py
[modify] https://crrev.com/e56e2bba7ccd18b1da071171909f326924eb0230/ios/build/bots/scripts/test_runner.py
[modify] https://crrev.com/e56e2bba7ccd18b1da071171909f326924eb0230/ios/build/bots/scripts/test_runner_test.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bcf3583c7dacd391109250d58eb5c705efc78df1

commit bcf3583c7dacd391109250d58eb5c705efc78df1
Author: Justin Cohen <justincohen@chromium.org>
Date: Tue Feb 20 17:03:37 2018

Revert "Implement iOS test sharding with multiple simulators on test_runner."

This reverts commit e56e2bba7ccd18b1da071171909f326924eb0230.

Reason for revert: Breaking downstream device tests:

Using Xcode version 9.2 build 9C40b at /b/swarm_slave/w/ir/Xcode.app/Contents/Developer
Traceback (most recent call last):
  File "src/ios/build/bots/scripts/run.py", line 228, in <module>
    sys.exit(main())
  File "src/ios/build/bots/scripts/run.py", line 73, in main
    return 0 if tr.launch() else 1
  File "/b/swarm_slave/w/ir/src/ios/build/bots/scripts/test_runner.py", line 489, in launch
    result = self._run(cmd=cmd, shards=self.shards or 1)
AttributeError: 'DeviceTestRunner' object has no attribute 'shards'



Original change's description:
> Implement iOS test sharding with multiple simulators on test_runner.
> 
> Details in doc:
> https://docs.google.com/document/d/1QaAZgmYuEImL1wAYJQxPcbex-fPLVd3rx8oMMKIgZX8/edit#
> 
> Bug:  808267 
> Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
> Change-Id: I55fc27fcf31120a7c9d39e8953f72a39dd6394a7
> Reviewed-on: https://chromium-review.googlesource.com/917309
> Commit-Queue: Menglu Huang <huangml@chromium.org>
> Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#537731}

TBR=sergeyberezin@chromium.org,huangml@chromium.org

Change-Id: I6a8e30d1fa5e9e1f5e2d7af3f620f967841cddcb
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug:  808267 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Reviewed-on: https://chromium-review.googlesource.com/926822
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537802}
[modify] https://crrev.com/bcf3583c7dacd391109250d58eb5c705efc78df1/ios/build/bots/scripts/run.py
[modify] https://crrev.com/bcf3583c7dacd391109250d58eb5c705efc78df1/ios/build/bots/scripts/test_runner.py
[modify] https://crrev.com/bcf3583c7dacd391109250d58eb5c705efc78df1/ios/build/bots/scripts/test_runner_test.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/89909a8e3ab2f965dfb57cd978d6f0af0e2934ea

commit 89909a8e3ab2f965dfb57cd978d6f0af0e2934ea
Author: Menglu Huang <huangml@chromium.org>
Date: Wed Feb 21 00:06:42 2018

Reland: Implement iOS test sharding with multiple simulators on test_runner.

Details in doc:
https://docs.google.com/document/d/1QaAZgmYuEImL1wAYJQxPcbex-fPLVd3rx8oMMKIgZX8/edit

Bug:  808267 

Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I7c39588168cf026e0433ffb26fe590ce78b44c8a
Reviewed-on: https://chromium-review.googlesource.com/926713
Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>
Commit-Queue: Menglu Huang <huangml@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537944}
[modify] https://crrev.com/89909a8e3ab2f965dfb57cd978d6f0af0e2934ea/ios/build/bots/scripts/run.py
[modify] https://crrev.com/89909a8e3ab2f965dfb57cd978d6f0af0e2934ea/ios/build/bots/scripts/test_runner.py
[modify] https://crrev.com/89909a8e3ab2f965dfb57cd978d6f0af0e2934ea/ios/build/bots/scripts/test_runner_test.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a82cf77fa857f61f52d3271992c0bdb4cd7623cc

commit a82cf77fa857f61f52d3271992c0bdb4cd7623cc
Author: Menglu Huang <huangml@chromium.org>
Date: Thu Feb 22 21:27:41 2018

Enable EarlGrey test sharding on waterfall

"shards": n allows test_runner to split tests into n shards and launch n simulators to run.
"shard size": n allows iOS recipe to isolate the test into smaller tasks.

Bug:  808267 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I250b0126e79ef2205850cf1ceb266906d8c87061
Reviewed-on: https://chromium-review.googlesource.com/930703
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>
Commit-Queue: Menglu Huang <huangml@chromium.org>
Cr-Commit-Position: refs/heads/master@{#538567}
[modify] https://crrev.com/a82cf77fa857f61f52d3271992c0bdb4cd7623cc/ios/build/bots/tests/eg_cq_tests.json
[modify] https://crrev.com/a82cf77fa857f61f52d3271992c0bdb4cd7623cc/ios/build/bots/tests/eg_tests.json