Add a ViewsDelegate to app_shell

This is in preparation for opening a v2 app window. We need a ViewsDelegate
so the views system can figure out where to parent the window.

BUG=341251
TEST=none

Review URL: https://codereview.chromium.org/156273002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249372 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 249372
Add AppListModel::MoveItemToFolderAt

This is necessary to allow items to be moved to a specific locaiton in
a folder (or in the top level model). 

This also updates MergeItems() to support source items inside folders.

This includes some cleanup to use scoped ptrs to document ownership of
items in AppListModel.


BUG=335761
For app_list.cc
TBR=jamescook@chromium.org

Review URL: https://codereview.chromium.org/152713003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249373 0039d316-1c4b-4281-b951-d872f2087c98
Quota: Remove ifdef macros used for callback cleanup

Depends on: https://codereview.chromium.org/135723009/


BUG=338995
TEST=compile

Review URL: https://codereview.chromium.org/155283003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249374 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 249374