Add a ClientAction used by SyncRollbackManager to notify PSS that rollback is

Add a ClientAction used by SyncRollbackManager to notify PSS that rollback is
finished.

BUG=362679
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=269615

[Nicolas Zea, 2014-05-07 17:11:10]

lgtm

[haitaol1, 2014-05-09 17:25:14]

The CQ bit was checked by haitaol@chromium.org

[commit-bot: I haz the power, 2014-05-09 17:26:37]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/haitaol@chromium.org/263273002/40001

[commit-bot: I haz the power, 2014-05-09 19:30:21]

FYI, CQ is re-trying this CL (attempt #1).
Please consider checking whether the failures are real,
and report flakes to chrome-troopers@google.com.
The failing builders are:
  linux_chromium_chromeos_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_chrome...)
  linux_chromium_chromeos_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_chrome...)
  linux_chromium_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_clang_...)
  linux_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_rel/bu...)
  mac_chromium_compile_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/mac_chromium_compile_...)
  mac_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/mac_chromium_rel/buil...)
  win_chromium_compile_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/win_chromium_compile_...)

[commit-bot: I haz the power, 2014-05-09 20:17:24]

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

[commit-bot: I haz the power, 2014-05-09 20:17:24]

Try jobs failed on following builders:
  linux_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_rel/bu...)

[haitaol1, 2014-05-09 21:46:16]

The CQ bit was checked by haitaol@chromium.org

[commit-bot: I haz the power, 2014-05-09 21:47:19]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/haitaol@chromium.org/263273002/60001

[commit-bot: I haz the power, 2014-05-10 19:11:54]

Change committed as 269615