unbreak the no-webrtc build

unbreak the no-webrtc build

Followup to https://codereview.chromium.org/1427003009

The third_party/libjingle/libjingle.gyp:libjingle_webrtc target is defined
inside an enable_webrtc==1 condition, so it can only be depended on inside
a similar condition.

BUG=547158
Committed: https://crrev.com/5938eeb0b396cca5014d73085fcb8c0d80cd20a5
Cr-Commit-Position: refs/heads/master@{#360646}

[Mostyn Bramley-Moore, 2015-11-19 05:19:17]

The CQ bit was checked by mostynb@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2015-11-19 05:19:51]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1457793004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1457793004/1

[Mostyn Bramley-Moore, 2015-11-19 05:20:42]

mostynb@opera.com changed reviewers:
+ kelvinp@chromium.org, sergeyu@chromium.org

[Mostyn Bramley-Moore, 2015-11-19 05:20:42]

@kelvinp, Sergey: please take a look at this fixup for CL1427003009.

[commit-bot: I haz the power, 2015-11-19 05:59:03]

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

[commit-bot: I haz the power, 2015-11-19 05:59:04]

Dry run: This issue passed the CQ dry run.

[Sergey Ulanov, 2015-11-19 19:43:38]

lgtm

[Sergey Ulanov, 2015-11-19 19:43:56]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2015-11-19 19:45:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1457793004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1457793004/1

[commit-bot: I haz the power, 2015-11-19 20:06:27]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-19 20:07:24]

Patchset 1 (id:??) landed as
https://crrev.com/5938eeb0b396cca5014d73085fcb8c0d80cd20a5
Cr-Commit-Position: refs/heads/master@{#360646}