Call |NavigationItemsPruned| when item is removed in session controller.

Call |NavigationItemsPruned| when item is removed in session controller.

|removeItemAtIndex| removes an item from CRWSessionController, so
|NavigationItemsPruned| should be called to notify observers.

BUG=

Review-Url: https://codereview.chromium.org/2774343004
Cr-Commit-Position: refs/heads/master@{#460009}
Committed: https://chromium.googlesource.com/chromium/src/+/2cc9de46038c9ed3d3959cece913d02759e6b9df

[liaoyuke, 2017-03-27 23:41:57]

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

[liaoyuke, 2017-03-27 23:42:38]

liaoyuke@chromium.org changed reviewers:
+ eugenebut@chromium.org

[liaoyuke, 2017-03-27 23:42:38]

Hey Eugene,

PTAL.

Thank you very much!

[commit-bot: I haz the power, 2017-03-27 23:42:45]

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, 2017-03-28 01:08:24]

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

[commit-bot: I haz the power, 2017-03-28 01:08:25]

Dry run: This issue passed the CQ dry run.

[Eugene But (OOO till 7-30), 2017-03-28 01:21:50]

lgtm

[liaoyuke, 2017-03-28 04:09:50]

The CQ bit was checked by liaoyuke@chromium.org

[commit-bot: I haz the power, 2017-03-28 04:10:05]

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, 2017-03-28 04:13:29]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1490674190924970, "parent_rev":
"204fb0fdcf7e0d30c645717d55d9d5c66f4d2ce3", "commit_rev":
"2cc9de46038c9ed3d3959cece913d02759e6b9df"}

[commit-bot: I haz the power, 2017-03-28 04:14:22]

Description was changed from

==========
Call |NavigationItemsPruned| when item is removed in session controller.

|removeItemAtIndex| removes an item from CRWSessionController, so
|NavigationItemsPruned| should be called to notify observers.

BUG=
==========

to

==========
Call |NavigationItemsPruned| when item is removed in session controller.

|removeItemAtIndex| removes an item from CRWSessionController, so
|NavigationItemsPruned| should be called to notify observers.

BUG=

Review-Url: https://codereview.chromium.org/2774343004
Cr-Commit-Position: refs/heads/master@{#460009}
Committed:
https://chromium.googlesource.com/chromium/src/+/2cc9de46038c9ed3d3959cece913...
==========

[commit-bot: I haz the power, 2017-03-28 04:14:23]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/2cc9de46038c9ed3d3959cece913...