Delete app_host from apps/

Delete app_host from apps/

This isn't used any more now and can be deleted. Chrome apps and the
chrome app launcher are now part of the main chrome install, and don't
need a separate executable to shunt control to chrome.

TBR=sky
BUG=279671
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=220555

[koz (OOO until 15th September), 2013-08-29 06:05:57]

wew! lgtm

[benwells, 2013-08-29 07:58:10]

There is more stuff in the installer to remove for this but this CL is a start.
I tested the installer with and without this change and it gives the same
warnings about the app launcher.

[Nico, 2013-08-29 17:22:11]

lgtm

[grt (UTC plus 2), 2013-08-30 02:45:15]

Could you clean up the references to app_host.exe and kChromeAppHostExe in
src/chrome/installer/*, and a TODO in
src/chrome/browser/ui/views/apps/native_app_window_views.cc, or do those need to
wait for a subsequent change? Thanks.

[grt (UTC plus 2), 2013-08-30 03:09:44]

On 2013/08/30 02:45:15, grt wrote:
> Could you clean up the references to app_host.exe and kChromeAppHostExe in
> src/chrome/installer/*, and a TODO in
> src/chrome/browser/ui/views/apps/native_app_window_views.cc, or do those need
to
> wait for a subsequent change? Thanks.

as per chat, lgtm with the TODO cleanup in this CL and installer cleanup in a
followon CL. thanks, ben.

[benwells, 2013-08-30 06:39:52]

TODO removed.
TBR sky for redundant TODO comment removal.

[commit-bot: I haz the power, 2013-08-30 06:40:35]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/benwells@chromium.org/23539002/19001

[commit-bot: I haz the power, 2013-08-30 12:03:53]

Change committed as 220555