Documents what ApplicationManager::Delegate do

Documents what ApplicationManager::Delegate do

And renames one to better indicate what it is expected to do.

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

Committed: https://crrev.com/70d52bc9323a077b1ce28afa1d12f69c129e13bd
Cr-Commit-Position: refs/heads/master@{#326847}

[sky, 2015-04-24 16:44:00]

Turns out we can't combine the two. Otherwise we wouldn't be able to set a
loader for a mojo url, which we need the ability to do. So, I've gone with
adding better documentation and renaming.

[Ben Goodger (Google), 2015-04-24 18:20:38]

lgtm

[sky, 2015-04-24 18:24:45]

The CQ bit was checked by sky@chromium.org

[commit-bot: I haz the power, 2015-04-24 18:25:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1052103005/40001

[commit-bot: I haz the power, 2015-04-24 18:44:29]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-04-24 18:45:20]

Patchset 3 (id:??) landed as
https://crrev.com/70d52bc9323a077b1ce28afa1d12f69c129e13bd
Cr-Commit-Position: refs/heads/master@{#326847}