Desktop capture: Fix GN target and exclude differ* sources on iOS

Desktop capture: Fix GN target and exclude differ* sources on iOS

Fix some out-of-sync differences between GYP and GN targets for
desktop capture.

Remove sources that aren't used on iOS for that platform, to solve
linking errors that surfaced when flipping iOS to GN by default.

BUG=webrtc:5949
NOTRY=True
TBR=sergeyu@chromium.org

Committed: https://crrev.com/131c958187352d52611256816bd12bd7d413d283
Cr-Commit-Position: refs/heads/master@{#13971}

[kjellander_webrtc, 2016-08-30 09:44:55]

kjellander@webrtc.org changed reviewers:
+ ehmaldonado@webrtc.org

[kjellander_webrtc, 2016-08-30 11:14:35]

The CQ bit was checked by kjellander@webrtc.org

[commit-bot: I haz the power, 2016-08-30 11:14:43]

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

[commit-bot: I haz the power, 2016-08-30 11:24:02]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-30 11:24:09]

Description was changed from

==========
Desktop capture: Fix GN target and exclude differ* sources on iOS

Fix some out-of-sync differences between GYP and GN targets for
desktop capture.

Remove sources that aren't used on iOS for that platform, to solve
linking errors that surfaced when flipping iOS to GN by default.

BUG=webrtc:5949
NOTRY=True
TBR=sergeyu@chromium.org
==========

to

==========
Desktop capture: Fix GN target and exclude differ* sources on iOS

Fix some out-of-sync differences between GYP and GN targets for
desktop capture.

Remove sources that aren't used on iOS for that platform, to solve
linking errors that surfaced when flipping iOS to GN by default.

BUG=webrtc:5949
NOTRY=True
TBR=sergeyu@chromium.org

Committed: https://crrev.com/131c958187352d52611256816bd12bd7d413d283
Cr-Commit-Position: refs/heads/master@{#13971}
==========

[commit-bot: I haz the power, 2016-08-30 11:24:10]

Patchset 1 (id:??) landed as
https://crrev.com/131c958187352d52611256816bd12bd7d413d283
Cr-Commit-Position: refs/heads/master@{#13971}