Reland "Convert webkit_unit_tests to swarming".

Reland of https://codereview.chromium.org/1341903002/

Convert webkit_unit_tests to run exclusively on Swarming

0 configs already ran on Swarming
43 used to run locally and were converted:
- chromium.fyi.json: ClangToTLinux tester
- chromium.fyi.json: ClangToTLinuxASan tester
- chromium.fyi.json: ClangToTMac tester
- chromium.fyi.json: ClangToTMacASan tester
- chromium.fyi.json: ClangToTWin tester
- chromium.fyi.json: ClangToTWin(dbg) tester
- chromium.fyi.json: ClangToTWin(dll) tester
- chromium.fyi.json: ClangToTWin64 tester
- chromium.fyi.json: ClangToTWin64(dbg) tester
- chromium.fyi.json: ClangToTWin64(dll) tester
- chromium.fyi.json: CrWinClang tester
- chromium.fyi.json: CrWinClang(dbg) tester
- chromium.fyi.json: CrWinClang(shared) tester
- chromium.fyi.json: CrWinClang64 tester
- chromium.fyi.json: CrWinClang64(dbg) tester
- chromium.fyi.json: CrWinClang64(dll) tester
- chromium.fyi.json: CrWinClangLLD tester
- chromium.webkit.json: WebKit Linux
- chromium.webkit.json: WebKit Linux (dbg)
- chromium.webkit.json: WebKit Linux 32
- chromium.webkit.json: WebKit Linux Leak
- chromium.webkit.json: WebKit Linux Oilpan
- chromium.webkit.json: WebKit Linux Oilpan (dbg)
- chromium.webkit.json: WebKit Linux Oilpan Leak
- chromium.webkit.json: WebKit Linux Trusty
- chromium.webkit.json: WebKit Mac Oilpan
- chromium.webkit.json: WebKit Mac Oilpan (dbg)
- chromium.webkit.json: WebKit Mac10.10
- chromium.webkit.json: WebKit Mac10.6
- chromium.webkit.json: WebKit Mac10.6 (dbg)
- chromium.webkit.json: WebKit Mac10.7
- chromium.webkit.json: WebKit Mac10.7 (dbg)
- chromium.webkit.json: WebKit Mac10.8
- chromium.webkit.json: WebKit Mac10.9
- chromium.webkit.json: WebKit Mac10.9 (retina)
- chromium.webkit.json: WebKit Win Oilpan
- chromium.webkit.json: WebKit Win Oilpan (dbg)
- chromium.webkit.json: WebKit Win x64 Builder
- chromium.webkit.json: WebKit Win x64 Builder (dbg)
- chromium.webkit.json: WebKit Win10
- chromium.webkit.json: WebKit Win7
- chromium.webkit.json: WebKit Win7 (dbg)
- chromium.webkit.json: WebKit XP

Ran:
  ./manage.py --convert webkit_unit_tests

TBR=maruel@chromium.org,dpranke@chromium.org
BUG=98637, 524758, 531819
NOTRY=true

Committed: https://crrev.com/aa2d8437ba50aeed8d3c104915d6bc3841a277f2
Cr-Commit-Position: refs/heads/master@{#349784}

[joelo, 2015-09-17 22:09:27]

joelo@chromium.org changed reviewers:
+ dpranke@chromium.org, maruel@chromium.org

[Dirk Pranke, 2015-09-17 23:09:04]

the trybots don't look happy ...

[joelo, 2015-09-17 23:10:34]

yea.. i forgot to wait for https://codereview.chromium.org/1352923003/ to land
before launching the tryjobs :/

[joelo, 2015-09-18 22:11:16]

The CQ bit was checked by joelo@chromium.org

[commit-bot: I haz the power, 2015-09-18 22:12:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1353523005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1353523005/1

[commit-bot: I haz the power, 2015-09-18 22:21:45]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-18 22:22:50]

Patchset 1 (id:??) landed as
https://crrev.com/aa2d8437ba50aeed8d3c104915d6bc3841a277f2
Cr-Commit-Position: refs/heads/master@{#349784}