mac: Fix bookmark drag and drop.

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

Index: chrome/browser/ui/cocoa/bookmarks/bookmark_button.h
diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_button.h b/chrome/browser/ui/cocoa/bookmarks/bookmark_button.h
index b968911674e6827d121da9e1f1dabe06cec73035..7fd62e78c552c094d5d9cf08ca5c4b590c3a2023 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_button.h
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_button.h
@@ -22,11 +22,8 @@ class BookmarkNode;
 // things on behalf of a bookmark button.
 @protocol BookmarkButtonDelegate
 
-// Fill the given pasteboard with appropriate data when the given button is
-// dragged. Since the delegate has no way of providing pasteboard data later,
-// all data must actually be put into the pasteboard and not merely promised.
-- (void)fillPasteboard:(NSPasteboard*)pboard
-       forDragOfButton:(BookmarkButton*)button;
+// Returns a pasteboard item that has all bookmark information.
+- (NSPasteboardItem*)pasteboardItemForDragOfButton:(BookmarkButton*)button;
 
 // Bookmark buttons pass mouseEntered: and mouseExited: events to
 // their delegate.  This allows the delegate to decide (for example)
@@ -56,6 +53,10 @@ class BookmarkNode;
 - (void)bookmarkDragDidEnd:(BookmarkButton*)button
                  operation:(NSDragOperation)operation;
 
+@optional
+// Called when a pasteboard drag is about to begin.
+- (void)willBeginPasteboardDrag;
+
 @end