Convert gpu_unittests to run exclusively on Swarming

Convert gpu_unittests to run exclusively on Swarming

13 configs already ran on Swarming
16 used to run locally and were converted:
- chromium.chromiumos.json: Linux ChromiumOS Ozone Tests (1)
- chromium.chromiumos.json: Linux ChromiumOS Tests (1)
- chromium.chromiumos.json: Linux ChromiumOS Tests (dbg)(1)
- chromium.fyi.json: CrWinAsan tester
- chromium.fyi.json: CrWinAsan(dll) tester
- chromium.fyi.json: Linux Trusty
- chromium.fyi.json: Linux Trusty (dbg)
- chromium.linux.json: Cast Linux
- chromium.memory.fyi.json: Linux ChromeOS MSan Tests
- chromium.memory.fyi.json: Linux MSan Tests
- chromium.memory.fyi.json: Linux TSan Tests
- chromium.memory.json: Linux ASan LSan Tests (1)
- chromium.memory.json: Linux Chromium OS ASan LSan Tests (1)
- chromium.memory.json: Mac ASan 64 Tests (1)
- chromium.webkit.json: Linux ChromiumOS Tests (1)
- chromium.webkit.json: Linux ChromiumOS Tests (dbg)(1)

Ran:
  ./manage.py --convert gpu_unittests

R=dpranke@chromium.org
BUG=98637
Committed: https://crrev.com/68c35b8e1664fa615414bac3e1a99ac617268c84
Cr-Commit-Position: refs/heads/master@{#336148}

[Dirk Pranke, 2015-06-24 00:45:17]

lgtm

[M-A Ruel, 2015-06-25 13:27:44]

The CQ bit was checked by maruel@chromium.org

[commit-bot: I haz the power, 2015-06-25 13:28:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1200233003/1

[commit-bot: I haz the power, 2015-06-25 14:34:34]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-25 14:36:30]

Patchset 1 (id:??) landed as
https://crrev.com/68c35b8e1664fa615414bac3e1a99ac617268c84
Cr-Commit-Position: refs/heads/master@{#336148}