chromeos: Add UMA stats for launcher and app list.

chromeos: Add UMA stats for launcher and app list.

Add the following UMA stats:
- Launcher_ClickOnAppListButton
  Count clicks on launcher's app list button.
- Launcher_ClickOnApp
  Count clicks on apps in launcher bar (including Chrome).
- AppList_ClickOnApp
  Count clicks on apps in app list bubble.
- AppList_Search
  Count search + open result in app list.
- AppList_ClickOnAppFromSearch
  Count clicks on apps in app list search results.

BUG=137358
TEST=Verify the added UMA stats work as expected.

R=sky@chromium.org

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=151156

[sky, 2012-08-10 19:04:34]

How come you're going with histograms instead of user actions?

[xiyuan, 2012-08-10 20:12:39]

On 2012/08/10 19:04:34, sky wrote:
> How come you're going with histograms instead of user actions?

I was not aware that we have RecordAction. :p

CL updated. Please take another look.

[sky, 2012-08-10 22:22:51]

LGTM

http://codereview.chromium.org/10832247/diff/5001/ash/shell_delegate.h
File ash/shell_delegate.h (right):

http://codereview.chromium.org/10832247/diff/5001/ash/shell_delegate.h#newcode48
ash/shell_delegate.h:48: UMA_LAUNCHER_CLICK_ON_APPLIST_BUTTON,
Can you sort all of these.

[commit-bot: I haz the power, 2012-08-10 22:36:34]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/xiyuan@chromium.org/10832247/5004

[commit-bot: I haz the power, 2012-08-10 23:54:06]

Change committed as 151156