Revert 206237 "Menu for the OSX app launcher, HoverImageMenuButt..."

Revert 206237 "Menu for the OSX app launcher, HoverImageMenuButt..."

Causes memory leaks in AppKit due to some obscure codepaths.

BUG=249630
> Menu for the OSX app launcher, HoverImageMenuButton in src/ui/base/cocoa/controls.
> 
> Adds a drop-down menu to the right of the search entry area on the OSX
> app launcher. The menu is shown when clicked, and the button responds to
> hover effects.
> 
> The menu button uses a new class, HoverImageMenuButton, which is derived
> from an NSPopUpButton with minor extensions. Notably, it does not have a
> dependency on browser themes, as does MenuButton from
> chrome/browser/ui/cocoa.  It tracks the mouse hover state and updates
> the cell, which extends NSPopUpButtonCell and shows only the image in
> the control frame -- no border, bezel, label, or dropdown arrow.
> 
> HoverImageMenuButtonCell supports a hover image, which behaves much like
> an additional 'alternateImage' from NSButtonCell but for the hover
> state, rather than the 'pressed' (or 'lit') state.
> 
> The menu shows the currently signed-in user, in a custom view as the
> first item. It also (currently) shows menu options for Settings, Help, and
> Feedback.
> 
> BUG=138633
> TEST=Added app_list_unittests AppsSearchBoxMenuTest and
> AppsSearchBoxMenuTest and tested manually to ensure the items are
> launched correctly. Added ui_unittests HoverImageMenuButtonTest.*
> 
> Review URL: https://chromiumcodereview.appspot.com/15955003

TBR=tapted@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=206375

[tapted, 2013-06-14 09:04:13]

Committed patchset #1 manually as r206375.