Switch to use Navigation events instead of provisional load events

One of the outstanding TODO items from our fix to redirect navigations to offline pages was to switch from the provisional load events to use the newer navigation events.

This change switches to the new events, and adds a working test.

BUG=591150
Committed: https://crrev.com/2ec1dfed7c0e8e9d29ce1c0366321426a8c1b489
Cr-Commit-Position: refs/heads/master@{#379725}

[Pete Williamson, 2016-03-02 16:41:49]

Description was changed from

==========
First attempt to fix unit tests


Single snackbar controller part 1


Don't show edit or reload snackbar after we are done reloading the page

In some cases, we were showing the reload snackbar long after we were
done with the offline version of the page.  It turns out we need to
detach the observer from the tab once we reload.

We also need to detatch the observer when the saved page is deleted.

BUG=582022,581670

patch from issue 1655993002 at patchset 180001
(http://crrev.com/1655993002#ps180001)
==========

to

==========
First attempt to fix unit tests


Single snackbar controller part 1


Don't show edit or reload snackbar after we are done reloading the page

In some cases, we were showing the reload snackbar long after we were
done with the offline version of the page.  It turns out we need to
detach the observer from the tab once we reload.

We also need to detatch the observer when the saved page is deleted.

BUG=582022,581670

patch from issue 1655993002 at patchset 180001
(http://crrev.com/1655993002#ps180001)
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
==========

[Pete Williamson, 2016-03-02 16:47:01]

Description was changed from

==========
First attempt to fix unit tests


Single snackbar controller part 1


Don't show edit or reload snackbar after we are done reloading the page

In some cases, we were showing the reload snackbar long after we were
done with the offline version of the page.  It turns out we need to
detach the observer from the tab once we reload.

We also need to detatch the observer when the saved page is deleted.

BUG=582022,581670

patch from issue 1655993002 at patchset 180001
(http://crrev.com/1655993002#ps180001)
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
==========

to

==========
First attempt to fix unit tests

Switch from using DidFailProvisionalLoad to DidFinishNavigation, including unit
tests
==========

[Pete Williamson, 2016-03-07 20:21:54]

Description was changed from

==========
First attempt to fix unit tests

Switch from using DidFailProvisionalLoad to DidFinishNavigation, including unit
tests
==========

to

==========
One of the outstanding TODO items from our fix to redirect navigations to
offline pages was to switch from the provisional load events to use the newer
navigation events.

This change switches to the new events, and adds a working test.

BUG=591150
==========

[Pete Williamson, 2016-03-07 20:21:55]

petewil@chromium.org changed reviewers:
+ jianli@chromium.org, nasko@chromium.org

[Pete Williamson, 2016-03-07 20:22:36]

JianLi@, Nasko@, this is working now, please take a look!  Thanks.

[nasko, 2016-03-07 23:21:27]

Thanks for following up on this and I'm sorry for the hassle that it was. I will
make a note to add some unit tests to show how those events can be used.

LGTM!

[jianli, 2016-03-08 00:09:00]

lgtm

[Pete Williamson, 2016-03-08 00:10:20]

The CQ bit was checked by petewil@chromium.org

[commit-bot: I haz the power, 2016-03-08 00:10:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1754333002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1754333002/40001

[commit-bot: I haz the power, 2016-03-08 01:54:36]

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

[commit-bot: I haz the power, 2016-03-08 01:54:37]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[Pete Williamson, 2016-03-08 01:55:12]

The CQ bit was checked by petewil@chromium.org

[commit-bot: I haz the power, 2016-03-08 01:55:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1754333002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1754333002/40001

[commit-bot: I haz the power, 2016-03-08 03:57:15]

Description was changed from

==========
One of the outstanding TODO items from our fix to redirect navigations to
offline pages was to switch from the provisional load events to use the newer
navigation events.

This change switches to the new events, and adds a working test.

BUG=591150
==========

to

==========
One of the outstanding TODO items from our fix to redirect navigations to
offline pages was to switch from the provisional load events to use the newer
navigation events.

This change switches to the new events, and adds a working test.

BUG=591150
==========

[commit-bot: I haz the power, 2016-03-08 03:57:16]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-03-08 03:59:26]

Description was changed from

==========
One of the outstanding TODO items from our fix to redirect navigations to
offline pages was to switch from the provisional load events to use the newer
navigation events.

This change switches to the new events, and adds a working test.

BUG=591150
==========

to

==========
One of the outstanding TODO items from our fix to redirect navigations to
offline pages was to switch from the provisional load events to use the newer
navigation events.

This change switches to the new events, and adds a working test.

BUG=591150

Committed: https://crrev.com/2ec1dfed7c0e8e9d29ce1c0366321426a8c1b489
Cr-Commit-Position: refs/heads/master@{#379725}
==========

[commit-bot: I haz the power, 2016-03-08 03:59:27]

Patchset 3 (id:??) landed as
https://crrev.com/2ec1dfed7c0e8e9d29ce1c0366321426a8c1b489
Cr-Commit-Position: refs/heads/master@{#379725}