Declare virtual destructor in Nacl plugin CallbackSource to fix mac build

Declare virtual destructor in Nacl plugin CallbackSource to fix mac build

R= ncbray@google.com,noelallen@google.com
BUG=none
TEST=mac nacl plugin scons build


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=142333

[Derek Schuff, 2012-06-14 21:16:12]

seems to work everywhere I tested it (including Nick's mac, which apparently
wasn't broken in the right way). PTAL

[Nick Bray, 2012-06-14 21:46:42]

LGTM

[commit-bot: I haz the power, 2012-06-14 23:42:53]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a lowly provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[noelallen1, 2012-06-14 23:47:43]

lgtm

[commit-bot: I haz the power, 2012-06-14 23:49:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dschuff@chromium.org/10536181/1

[commit-bot: I haz the power, 2012-06-14 23:50:00]

Presubmit check for 10536181-1 failed and returned exit status 1.

Running presubmit commit checks ...

** Presubmit ERRORS **
Missing LGTM from an OWNER for files in these directories:
    ppapi/native_client

Was the presubmit check useful? Please send feedback & hate mail to
maruel@chromium.org!

[jvoung - send to chromium..., 2012-06-14 23:55:01]

lgtm

[commit-bot: I haz the power, 2012-06-14 23:55:46]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dschuff@chromium.org/10536181/1

[commit-bot: I haz the power, 2012-06-15 03:40:26]

Change committed as 142333