[Sync] Ensure RegisterWithBackend is only called for correct types

[Sync] Ensure RegisterWithBackend is only called for correct types

RegisterWithBackend prepares USS datatype for syncing by triggering creation
of ModelTypeWorker. It should only be called for type that just successfully
finished LoadModels.

BUG=655389, 658443
R=skym@chromium.org

Committed: https://crrev.com/4e96ec4910903cb2a3b5e7ce27263723f2a725d9
Cr-Commit-Position: refs/heads/master@{#427498}

[pavely, 2016-10-25 18:39:34]

The CQ bit was checked by pavely@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-10-25 18:40:12]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-25 19:41:30]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-10-25 19:41:31]

Dry run: This issue passed the CQ dry run.

[skym, 2016-10-25 19:45:04]

lgtm

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
File components/sync/driver/data_type_manager_impl.cc (right):

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl.cc:173:
DCHECK(!data_type_status_table_.GetFailedTypes().Has(dtc->type()));
Can you add a big comment explaining why this DCHECK is reasonable?

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
File components/sync/driver/data_type_manager_impl_unittest.cc (right):

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl_unittest.cc:1681:
TEST_F(SyncDataTypeManagerImplTest, Slon) {
Slon?

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl_unittest.cc:1682: // Initiate
configuration for two datatypes but block them at LodaModels.
LoadModels

[pavely, 2016-10-25 20:49:12]

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
File components/sync/driver/data_type_manager_impl.cc (right):

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl.cc:173:
DCHECK(!data_type_status_table_.GetFailedTypes().Has(dtc->type()));
On 2016/10/25 19:45:04, skym wrote:
> Can you add a big comment explaining why this DCHECK is reasonable?

Done.

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
File components/sync/driver/data_type_manager_impl_unittest.cc (right):

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl_unittest.cc:1681:
TEST_F(SyncDataTypeManagerImplTest, Slon) {
On 2016/10/25 19:45:04, skym wrote:
> Slon?

Ugh.... Sorry.
Done.

https://codereview.chromium.org/2448863004/diff/1/components/sync/driver/data...
components/sync/driver/data_type_manager_impl_unittest.cc:1682: // Initiate
configuration for two datatypes but block them at LodaModels.
On 2016/10/25 19:45:04, skym wrote:
> LoadModels

Done.

[pavely, 2016-10-25 20:49:15]

The CQ bit was checked by pavely@chromium.org

[pavely, 2016-10-25 20:49:15]

The patchset sent to the CQ was uploaded after l-g-t-m from skym@chromium.org
Link to the patchset: https://codereview.chromium.org/2448863004/#ps20001
(title: "Address Sky's comments.")

[commit-bot: I haz the power, 2016-10-25 20:49:53]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-25 21:59:13]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-10-25 22:02:41]

Description was changed from

==========
[Sync] Ensure RegisterWithBackend is only called for correct types

RegisterWithBackend prepares USS datatype for syncing by triggering creation
of ModelTypeWorker. It should only be called for type that just successfully
finished LoadModels.

BUG=655389,658443
R=skym@chromium.org
==========

to

==========
[Sync] Ensure RegisterWithBackend is only called for correct types

RegisterWithBackend prepares USS datatype for syncing by triggering creation
of ModelTypeWorker. It should only be called for type that just successfully
finished LoadModels.

BUG=655389,658443
R=skym@chromium.org

Committed: https://crrev.com/4e96ec4910903cb2a3b5e7ce27263723f2a725d9
Cr-Commit-Position: refs/heads/master@{#427498}
==========

[commit-bot: I haz the power, 2016-10-25 22:02:42]

Patchset 2 (id:??) landed as
https://crrev.com/4e96ec4910903cb2a3b5e7ce27263723f2a725d9
Cr-Commit-Position: refs/heads/master@{#427498}