Change AckEvent into request / response

Change AckEvent into request / response

BUG=None

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=260635

[DaveMoore, 2014-03-30 22:26:19]

Note: I made a change to the semantics of the request / response. It used to
only call ack for input events. Each implementation of the client was
responsible for this logic. It seemed better to call it all the time. It looks
safe to me, but events are only generated on Android, and the app no longer runs
there (turns out that was true even before my changes at the end of the week).
I'm going to investigate that separately, but it means I can't test this there
yet.

[darin (slow to review), 2014-03-31 03:24:04]

LGTM

https://codereview.chromium.org/218763002/diff/1/mojo/examples/pepper_contain...
File mojo/examples/pepper_container_app/pepper_container_app.cc (right):

https://codereview.chromium.org/218763002/diff/1/mojo/examples/pepper_contain...
mojo/examples/pepper_container_app/pepper_container_app.cc:95: if
(event.location().is_null())
it might be good to leave a comment here checking if it makes sense to suppress
the callback in this case. the caller of OnEvent will be left hanging if we
return early here. is that ok?

https://codereview.chromium.org/218763002/diff/1/mojo/services/native_viewpor...
File mojo/services/native_viewport/native_viewport_service.cc (right):

https://codereview.chromium.org/218763002/diff/1/mojo/services/native_viewpor...
mojo/services/native_viewport/native_viewport_service.cc:150:
base::Unretained(this)));
I believe this use of base::Unretained is OK here because the enqueue'd
callbacks can only run if the RemotePtr member of Service<..> remains valid. I
wonder if we shouldn't find some way to make this more apparent. Hmm...

[DaveMoore, 2014-03-31 16:28:16]

Fix early return

[DaveMoore, 2014-03-31 16:28:24]

The CQ bit was checked by davemoore@chromium.org

[commit-bot: I haz the power, 2014-03-31 16:29:04]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/davemoore@chromium.org/218763002/20001

[commit-bot: I haz the power, 2014-03-31 20:33:39]

Change committed as 260635