GTK: implement extension bookmark manager drag api....

chrome/browser/cocoa/web_drop_target.mm

Index: chrome/browser/cocoa/web_drop_target.mm
===================================================================
--- chrome/browser/cocoa/web_drop_target.mm	(revision 41880)
+++ chrome/browser/cocoa/web_drop_target.mm	(working copy)
@@ -5,6 +5,7 @@
 #import "chrome/browser/cocoa/web_drop_target.h"
 
 #include "base/sys_string_conversions.h"
+#include "chrome/browser/bookmarks/bookmark_drag_data.h"
 #include "chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
@@ -82,8 +83,9 @@
   // If the tab is showing the boomark manager, send BookmarkDrag events
   RenderViewHostDelegate::BookmarkDrag* dragDelegate =
       tabContents_->GetBookmarkDragDelegate();
-  if(dragDelegate)
-    dragDelegate->OnDragEnter(NULL);
+  BookmarkDragData dragData;
+  if(dragDelegate && dragData.ReadFromDragClipboard())
+    dragDelegate->OnDragEnter(dragData);
 
   // Fill out a WebDropData from pasteboard.
   WebDropData data;
@@ -142,8 +144,9 @@
   // If the tab is showing the boomark manager, send BookmarkDrag events
   RenderViewHostDelegate::BookmarkDrag* dragDelegate =
       tabContents_->GetBookmarkDragDelegate();
-  if(dragDelegate)
-    dragDelegate->OnDragOver(NULL);
+  BookmarkDragData dragData;
+  if(dragDelegate && dragData.ReadFromDragClipboard())
+    dragDelegate->OnDragOver(dragData);
   return current_operation_;
 }
 
@@ -168,8 +171,9 @@
   // If the tab is showing the boomark manager, send BookmarkDrag events
   RenderViewHostDelegate::BookmarkDrag* dragDelegate =
       tabContents_->GetBookmarkDragDelegate();
-  if(dragDelegate)
-    dragDelegate->OnDrop(NULL);
+  BookmarkDragData dragData;
+  if(dragDelegate && dragData.ReadFromDragClipboard())
+    dragDelegate->OnDrop(dragData);
 
   currentRVH_ = NULL;