Revert 235935 "Reland - [ash] Enable dragging an item between sh..."

> Reland - [ash] Enable dragging an item between shelf and overflow bubble
> 
> Previous cl (https://codereview.chromium.org/61703002/) was reverted
> because win8-aura doesn't support multiple display.
> 
> Description Copied from original cl:
> This is the first CL to implement drag and drop from overflow bubble to shelf.
> 
> Currently ripped off item from overflow bubble cannot be dragged into shelf.
> But, Item should be dragged from overflow bubble to shelf to implement drag & drop.
> In this CL, re-insert bounds for shelf/overflow bubble is re-defined like below.
> - shelf -bounds that include visible items.
> - overflow bubble - overflow bubble bounds.
> 
> * The method of ripping off is not changed (dragging an item to above only in bottom alignment)
> If ripping off is possible by dragging to down side, it could cause flickering because overflow bubble and shelf is located too closely.
> 
> R=jamescook@chromium.org
> BUG=137141
> TEST=ash_unittest --gtest_filter=*.CheckDragInsertBoundsWithMultiMonitor
> 
> Review URL: https://codereview.chromium.org/74853002

TBR=simonhong@chromium.org

Review URL: https://codereview.chromium.org/73233003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235947 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 235947