Implement a mostly working InfoBubble with a shim BookmarkBubble.

chrome/browser/gtk/browser_window_gtk.cc

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/gtk/browser_window_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 
 #include "base/base_paths_linux.h"
 #include "base/command_line.h"
@@ skipping 469 matching lines @@
 void BrowserWindowGtk::ShowAboutChromeDialog() {
   ShowAboutDialogForProfile(window_, browser_->profile());
 }
 
 void BrowserWindowGtk::ShowBookmarkManager() {
   NOTIMPLEMENTED();
 }
 
 void BrowserWindowGtk::ShowBookmarkBubble(const GURL& url,
                                           bool already_bookmarked) {
-  NOTIMPLEMENTED();
+  toolbar_->star()->ShowStarBubble(url, !already_bookmarked);
 }
 
 void BrowserWindowGtk::ShowReportBugDialog() {
   NOTIMPLEMENTED();
 }
 
 void BrowserWindowGtk::ShowClearBrowsingDataDialog() {
   NOTIMPLEMENTED();
 }
 
@@ skipping 204 matching lines @@
   } else {
     browser_window->ExecuteBrowserCommand(command_id);
   }
 
   return TRUE;
 }
 
 void BrowserWindowGtk::ExecuteBrowserCommand(int id) {
   browser_->ExecuteCommand(id);
 }