Filter out the network in networkmonitor if the linkProperties is null.

Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are pretty much the same for logging but network.toString does not need to parse the int value.

BUG=

Committed: https://crrev.com/97aacee11d21caa4ca9c40c493aeba6940a7c063
Cr-Commit-Position: refs/heads/master@{#11925}

[honghaiz3, 2016-03-09 01:40:42]

Description was changed from

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.

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

to

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are
pretty much the same for logging but network.toString does not need to parse the
int value.

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

[honghaiz3, 2016-03-09 01:43:33]

honghaiz@webrtc.org changed reviewers:
+ glaznev@webrtc.org

[AlexG, 2016-03-09 03:29:28]

lgtm

[honghaiz3, 2016-03-09 03:37:25]

The CQ bit was checked by honghaiz@webrtc.org

[commit-bot: I haz the power, 2016-03-09 03:37:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1774343002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1774343002/1

[commit-bot: I haz the power, 2016-03-09 04:50:03]

Description was changed from

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are
pretty much the same for logging but network.toString does not need to parse the
int value.

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

to

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are
pretty much the same for logging but network.toString does not need to parse the
int value.

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

[commit-bot: I haz the power, 2016-03-09 04:50:03]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-09 04:50:11]

Description was changed from

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are
pretty much the same for logging but network.toString does not need to parse the
int value.

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

to

==========
Filter out the network in networkmonitor if the linkProperties is null.
It may be null if the network is unknown.
Also revised the logging to replace network id with network.toString(). They are
pretty much the same for logging but network.toString does not need to parse the
int value.

BUG=

Committed: https://crrev.com/97aacee11d21caa4ca9c40c493aeba6940a7c063
Cr-Commit-Position: refs/heads/master@{#11925}
==========

[commit-bot: I haz the power, 2016-03-09 04:50:11]

Patchset 1 (id:??) landed as
https://crrev.com/97aacee11d21caa4ca9c40c493aeba6940a7c063
Cr-Commit-Position: refs/heads/master@{#11925}