Save memory in the downloads extension API.

Save memory in the downloads extension API.
EDERD is only necessary if there are extensions listening for either onChanged or onDeterminingFilename.

BUG=224332
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195233

[benjhayden, 2013-04-16 20:07:41]

I seem to recall you saying that HasEventListeners was not as good as
will_dispatch_callback for some reason back when I implemented
onDeterminingFilename.
Is HasEventListeners a sufficient way to determine whether there are any
listeners, or do I need to figure out something involving will_dispatch_callback
and/or OnListenerAdded?

[not at google - send to devlin, 2013-04-17 01:33:09]

I'm going to punt this to mpcomplete because I don't remember saying that, but
it sounds like the kind of thing that Matt would say...

[Matt Perry, 2013-04-17 02:01:28]

HasEventListener is the right thing to use here. will_dispatch_callback was
useful for handling incognito specially, but we don't need to do that here.

LGTM with the style issues fixed.

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
File chrome/browser/extensions/api/downloads/downloads_api.cc (right):

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
chrome/browser/extensions/api/downloads/downloads_api.cc:1329:
extensions::event_names::kOnDownloadDeterminingFilename);
nit: might help to put
  namespace events = extensions::event_names
at the top to shorten all these refs.

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
chrome/browser/extensions/api/downloads/downloads_api.cc:1331: event_router();
Use 4 space indent when wrapping a line like this.

[benjhayden, 2013-04-18 18:17:55]

Thanks!

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
File chrome/browser/extensions/api/downloads/downloads_api.cc (right):

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
chrome/browser/extensions/api/downloads/downloads_api.cc:1329:
extensions::event_names::kOnDownloadDeterminingFilename);
On 2013/04/17 02:01:28, Matt Perry wrote:
> nit: might help to put
>   namespace events = extensions::event_names
> at the top to shorten all these refs.

Done.

https://codereview.chromium.org/14308002/diff/11001/chrome/browser/extensions...
chrome/browser/extensions/api/downloads/downloads_api.cc:1331: event_router();
On 2013/04/17 02:01:28, Matt Perry wrote:
> Use 4 space indent when wrapping a line like this.

Done.

[commit-bot: I haz the power, 2013-04-19 12:39:47]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/benjhayden@chromium.org/14308002/1006

[commit-bot: I haz the power, 2013-04-19 12:40:49]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=ios_dbg_si...

[commit-bot: I haz the power, 2013-04-19 14:36:37]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/benjhayden@chromium.org/14308002/21004

[commit-bot: I haz the power, 2013-04-19 18:04:49]

Change committed as 195233