app_list: Touch scroll and animation improvement.

app_list: Touch scroll and animation improvement.

- Use layer for AppListItemView for smoother animation and scroll transition;
- Support reverse current animation in SelectPage so that we don't need to reset
  current animation on fling gesture;
- Change fling speed threshold from 1100 to 800;
- Lower finish transition threshold from 0.5 to 0.33;
- Increase transition animation during from default 120ms to 180ms;
- Use linear tween type for transition animation;

Piggy backed with the change:
- Change app menu background from #fcfcfc to #f5f5f5

BUG=145580
TEST=Manual, touch scroll and page transition animation should be smoother and more natural. App menu background is darker.

R=sky@chromium.org


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=154106

[sky, 2012-08-30 00:24:57]

LGTM

[commit-bot: I haz the power, 2012-08-30 04:24:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/xiyuan@chromium.org/10890049/2001

[commit-bot: I haz the power, 2012-08-30 05:53:42]

Try job failure for 10890049-2001 (retry) on linux_rel for step
"interactive_ui_tests".
It's a second try, previously, step "interactive_ui_tests" failed.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_rel&...

[commit-bot: I haz the power, 2012-08-30 07:24:43]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/xiyuan@chromium.org/10890049/2001

[commit-bot: I haz the power, 2012-08-30 09:53:29]

Change committed as 154106