[Sync] Split model association into multiple UI tasks

[Sync] Split model association into multiple UI tasks

UI datatypes perform model association synchronously without any
chance of intervening tasks. This change posts the association
task for each datatype, allowing other work to intervene, both reducing
jank as well as allowing OOM warnings to be processed on platforms that
support them.

BUG=458406
Committed: https://crrev.com/3f4a998b6547fc32939f74fad8ecca1539705f7b
Cr-Commit-Position: refs/heads/master@{#321859}

[Nicolas Zea, 2015-03-20 21:34:20]

zea@chromium.org changed reviewers:
+ pavely@chromium.org

[Nicolas Zea, 2015-03-20 21:34:21]

+Pavel, PTAL

[pavely, 2015-03-20 23:35:25]

lgtm with comment about unittest.

https://codereview.chromium.org/1024223002/diff/1/chrome/browser/sync/glue/fr...
File chrome/browser/sync/glue/frontend_data_type_controller_unittest.cc (right):

https://codereview.chromium.org/1024223002/diff/1/chrome/browser/sync/glue/fr...
chrome/browser/sync/glue/frontend_data_type_controller_unittest.cc:192:
EXPECT_EQ(DataTypeController::NOT_RUNNING, frontend_dtc_->state());
PumpLoop() here as well?

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
File components/sync_driver/ui_data_type_controller_unittest.cc (right):

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
components/sync_driver/ui_data_type_controller_unittest.cc:138: Start();
I think you need PumLoop() here to exercise code.

[Nicolas Zea, 2015-03-23 20:20:33]

New patchset fixing the tests (hopefully). PTAL

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
File components/sync_driver/ui_data_type_controller_unittest.cc (right):

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
components/sync_driver/ui_data_type_controller_unittest.cc:138: Start();
On 2015/03/20 23:35:25, pavely wrote:
> I think you need PumLoop() here to exercise code.

PumpLoop is part of Start() above. Unless you mean we need it twice? Note that
these tests are passing, the failures are in the datatype specific tests I
forgot to update (newest patchset has them).

[pavely, 2015-03-23 20:26:25]

lgtm

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
File components/sync_driver/ui_data_type_controller_unittest.cc (right):

https://codereview.chromium.org/1024223002/diff/1/components/sync_driver/ui_d...
components/sync_driver/ui_data_type_controller_unittest.cc:138: Start();
On 2015/03/23 20:20:33, Nicolas Zea wrote:
> On 2015/03/20 23:35:25, pavely wrote:
> > I think you need PumLoop() here to exercise code.
> 
> PumpLoop is part of Start() above. Unless you mean we need it twice? Note that
> these tests are passing, the failures are in the datatype specific tests I
> forgot to update (newest patchset has them).

You are right. I was looking at Start() in my local file.

[Nicolas Zea, 2015-03-23 20:27:13]

The CQ bit was checked by zea@chromium.org

[commit-bot: I haz the power, 2015-03-23 20:29:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1024223002/20001

[commit-bot: I haz the power, 2015-03-23 21:35:22]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-23 21:36:05]

Patchset 2 (id:??) landed as
https://crrev.com/3f4a998b6547fc32939f74fad8ecca1539705f7b
Cr-Commit-Position: refs/heads/master@{#321859}