Nukes MessageLoop::Dispatcher

Nukes MessageLoop::Dispatcher

There is no point in this typedef now that MessagePumpDispatcher is
its own class.

BUG=none
TEST=none
R=ben@chromium.org, darin@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=245226

[sky, 2014-01-15 16:30:34]

darin: base
ben: the rest

[Ben Goodger (Google), 2014-01-15 19:09:52]

Cool! LGTM for the conversions.

[darin (slow to review), 2014-01-15 19:12:56]

base/ LGTM

[commit-bot: I haz the power, 2014-01-15 21:47:11]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sky@chromium.org/139593002/1

[commit-bot: I haz the power, 2014-01-15 23:49:42]

Retried try job too often on win_rel for step(s) app_list_unittests,
ash_unittests, aura_unittests, cacheinvalidation_unittests, cc_unittests,
check_deps, check_deps2git, chrome_elf_unittests, chromedriver_unittests,
components_unittests, compositor_unittests, content_browsertests,
content_unittests, crypto_unittests, events_unittests, google_apis_unittests,
gpu_unittests, installer_util_unittests, ipc_tests, jingle_unittests,
media_unittests, mini_installer_test, nacl_integration, ppapi_unittests,
printing_unittests, remoting_unittests, sql_unittests, sync_integration_tests,
sync_unit_tests, telemetry_unittests, views_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2014-01-16 02:12:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sky@chromium.org/139593002/1

[commit-bot: I haz the power, 2014-01-16 04:04:40]

Retried try job too often on win_x64_rel for step(s) base_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_x64_re...

[sky, 2014-01-16 17:25:14]

Committed patchset #1 manually as r245226 (presubmit successful).