[Mac] Restore the old bookmark menus now that the experiment is over.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_hover_state.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import <Cocoa/Cocoa.h>
+
+#include "base/memory/scoped_nsobject.h"
+#import "chrome/browser/ui/cocoa/bookmarks/bookmark_button.h"
+
+// Hover state machine.  Encapsulates the hover state for
+// BookmarkBarFolderController.
+// A strict call order is implied with these calls.  It is ONLY valid to make
+// the following state transitions:
+// From:            To:               Via:
+// closed           opening           scheduleOpen...:
+// opening          closed            cancelPendingOpen...: or
+//                  open              scheduleOpen...: completes.
+// open             closing           scheduleClose...:
+// closing          open              cancelPendingClose...: or
+//                  closed            scheduleClose...: completes.
+//
+@interface BookmarkBarFolderHoverState : NSObject {
+ @private
+  // Enumeration of the valid states that the |hoverButton_| member can be in.
+  // Because the opening and closing of hover views can be done asyncronously
+  // there are periods where the hover state is in transtion between open and
+  // closed.  During those times of transition the opening or closing operation
+  // can be cancelled.  We serialize the opening and closing of the
+  // |hoverButton_| using this state information.  This serialization is to
+  // avoid race conditions where one hover button is being opened while another
+  // is closing.
+  enum HoverState {
+    kHoverStateClosed = 0,
+    kHoverStateOpening = 1,
+    kHoverStateOpen = 2,
+    kHoverStateClosing = 3
+  };
+
+  // Like normal menus, hovering over a folder button causes it to
+  // open.  This variable is set when a hover is initiated (but has
+  // not necessarily fired yet).
+  scoped_nsobject<BookmarkButton> hoverButton_;
+
+  // We model hover state as a state machine with specific allowable
+  // transitions.  |hoverState_| is the state of this machine at any
+  // given time.
+  HoverState hoverState_;
+}
+
+// Designated initializer.
+- (id)init;
+
+// The BookmarkBarFolderHoverState decides when it is appropriate to hide
+// and show the button that the BookmarkBarFolderController drags over.
+- (NSDragOperation)draggingEnteredButton:(BookmarkButton*)button;
+
+// The BookmarkBarFolderHoverState decides the fate of the hover button
+// when the BookmarkBarFolderController's view is exited.
+- (void)draggingExited;
+
+@end
+
+// Exposing these for unit testing purposes.  They are used privately in the
+// implementation as well.
+@interface BookmarkBarFolderHoverState(PrivateAPI)
+// State change APIs.
+- (void)scheduleCloseBookmarkFolderOnHoverButton;
+- (void)cancelPendingCloseBookmarkFolderOnHoverButton;
+- (void)scheduleOpenBookmarkFolderOnHoverButton:(BookmarkButton*)hoverButton;
+- (void)cancelPendingOpenBookmarkFolderOnHoverButton;
+@end
+
+// Exposing these for unit testing purposes.  They are used only in tests.
+@interface BookmarkBarFolderHoverState(TestingAPI)
+// Accessors and setters for button and hover state.
+- (BookmarkButton*)hoverButton;
+- (HoverState)hoverState;
+@end